BIO INFORMATICS - III B.Tech II Semester Supplymentary Examinations,AUGUST 2007

JNTU old question papers 2007

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BIO INFORMATICS - IV B.Tech II Semester Examinations,AUGUST 2011

Code No: 07A81204 R07 Set No. 2

IV B.Tech II Semester Examinations,AUGUST 2011
BIO INFORMATICS
Information Technology

Time: 3 hours Max Marks: 80

Answer any FIVE Questions
All Questions carry equal marks

? ? ? ? ?

1. Explain the applications of multiple sequence alignments. [16]

2. Discuss about the significance of using scoring matrices in sequence alignment.[16]

3. Write short notes on:
(a) Russel Wallace
(b) Charles Darwin. [8+8]

4. Discuss the applications of PDB files with one example. [16]

5. Discuss the search parameter criteria in Swissprot with one example. [16]

6. What is Bioinformatics? Describe its scope in modern biology? [16]

7. Describe in brief about the tool SWISS MODELLER available at EXPASY with
one example. [16]
8. Write short notes on:
(a) Positional cloning approach.
(b) Candidate Gene approach. [8+8]


***********

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Credit Card Agreements Easier to Understand Than Facebook, Google Policies

Just how complex are those user agreements that most people skip reading when they sign up for Facebook or Google?

More complex than a credit card agreement or a government notice, according to a study released Tuesday by branding firm Siegel+Gale. On average, 400 survey participants who had carefully reviewed the agreements were only able to answer four out of 10 comprehension questions about the policies after their review.

What's worse, of users who did understand the policies or had them explained to them, 75% said they would change their Facebook privacy settings and 63% said they would be more careful about how they used Google in the future.

'It's time for these online giants to recognize that their policies bring an unacceptable web of complexity and risk to the lives of their users. The lack of understanding of online privacy is pervasive,' said Thomas Mueller, global director of customer experience of Siegel+Gale. 'Bringing greater simplicity to what Web users read online will engender trust among users and only benefit Facebook's and Google's reputation.'

Among the study's other key findings:

• The comprehension rates for credit card agreements (70%) and government notices (67%) were far higher than those for Google (36%) and Facebook (39%).


• Just one in five Facebook users were able to figure out how to block a third-party application or website from accessing information they shared on Facebook after reading the social network's privacy policy.


• Less than one in four Google+ users could figure out whether their profile was publicly viewable to anyone after reading Google's privacy terms.

All of these issues are compounded by the fact that privacy policies, particularly those used by social networks, are ever-evolving and ever-changing. Even if a user can understand a privacy policy, it can - especially in the case of Facebook - change without their knowledge. 

'This complexity erodes trust and jeopardizes online privacy,' said Irene Etzkorn, executive director of simplification of Siegel+Gale. 'Clearly, Facebook, Google and other online service providers operate based on consumer trust, and failure to address privacy concerns in a meaningful way will lead to consumer disenchantment and additional regulatory restrictions.'

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State Bank of India launches virtual debit card to curb fraud in ecommerce transactions

The State Bank of India (SBI) has introduced a virtual debit card called State Bank Virtual to address the users’ concern about debit card fraud while doing ecommerce transactions. The electronic card can be created by the account holder or customer using SBI's Net banking facility for ecommerce transactions. State Bank Virtual has a limited shelf life and can be used for only one transaction to limit the exposure of the account.

It allows the user to create a virtual card for any online transaction and the person is not required to share details of the principal account on the merchant Website thus insulating the account from any possible fraud.

There is no charge on creation of the card and the customer can create any number of cards at the same time. The card is created for each online transaction and is valid for maximum of 48 hours. There is no transfer of balance from the principal account in as much as only a lien is marked on the account. Actual transfer of balance takes place only when the customer does the actual transaction online, SBI said.

"All forms of transactions, be it Internet banking, credit and debit cards, are fully secured but there are some people who are scared and hold back from online transactions on fears of compromise of data. The main objective behind this new product is to provide relief to these customers and give a push to e-commerce," Richhpal Singh, DGM, Payment Systems, SBI has said in a statement.

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How Google Searches the Entire Web in Half a Second

It only takes half a second for Google to return a search based on keywords you type in, but there’s a whole lot more happening behind the scenes to give you the results you need. Google on Monday launched a video that explains the science behind how the massive search engine actually works.

Matt Cutts, software engineer head of Google’s webspam team, details in a YouTube video how the search engine giant thoroughly scours the web on a daily basis to provide the most up-to-date results to users.

“There are three things you need to do to be the best search engine in the world. First, you need to crawl the web comprehensively and deeply, then you want to rank or serve those pages and return the most relevant ones first,” Cutts said.

Although Google crawls the web on a daily basis, that wasn’t always the case.

“We used to crawl for 30 days… and then index for about a week and push that data out — and that would take about a week,” Cutts said. “Sometimes you would hit a data center with new data and sometimes you would hit a data center with old data.”

But this method wasn’t optimized since a lot of the information would be out of date. In 2003, Google switched to crawling a significant amount of the Internet each day. By scouring the web each day for new content, it incrementally updated its index.

“We have gotten even better over time, and at this point, we can keep it very fresh,” Cutts said.

To do so, page rank is the key deciding factor as to how likely you are to see a link: “We basically take page rank as the primary determinant and the more page rank you have — that is, the more people that link to you and the more reputable those people are — the more likely it is that we will discover your page relatively early in the crawl,” Cutts said.

Google also places a lot of emphasis on word order. For example, a search for pop singer “Katy Perry” will look for results with those two words next to each other, rather than having “Katy” and the word “Perry” show up in different parts of the content.

Finding the right balance between word proximity, page reputation and links pointing to it is the key.

“That’s kind of the secret sauce,” Cutt added.

Google then sends that query out to hundreds of different machines all at once, which look through their fraction of the web that has been indexed to find the best match.

“We say, ‘what’s the best page that matches this query across our entire index?” Cutts said. “We take that page and we try to show it with a useful snippet, so we show the keywords in the context of the document and get it all back in under half a second.”

How do you think companies can use this information to better show up in Google search results? Let us know your thoughts in the comments.

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Custom ORDER BY For SQL Server

Semester Based Custom ORDER BY For SQL Server

Working with lots of academic data I often have the need to sort based on the semester.  Here is a quick sample of how to build a custom order by list that will give you ordered results based on the semester (in descending order)

ORDER BY
    ACADEMIC_YEAR DESC,
    CASE ACADEMIC_TERM
        WHEN 'WINTER' THEN 1
        WHEN 'FALL' THEN 2
        WHEN 'SUMMER' THEN 3
        WHEN 'SPRING' THEN 4
    END

-------------------------------------------------------------------------------------------

Defining a Custom ORDER BY Sort Order
The SQL ORDER BY clause is very useful to sort your results quickly and easily. An underlying problem with ORDER BY is that, in its simplest implementation, we are quite limited to how it actually functions. We leave the SQL Engine of our database of choice to decide what the order is. Typically we could use the ORDER BY clause to either modify the sort order -




SELECT * FROM EMPLOYEES ORDER BY EMP_ID [ASC|DESC]

or even numerically order the columns to sort based on the SELECT clause -




SELECT EMP_ID, NAME FROM EMPLOYEES ORDER BY 1,2

These approaches give us some control over how this clause functions, however it isn't very friendly or functional when we have very specific needs. What if we need to specify a custom order that the basic functions of ORDER BY are incapable of?

Using our Employee example again, what if we need to order by a specific seniority level - say we want the supervisors to appear first, then associates, then executives. We may get lucky with a standard ORDER BY, but odds are it won't work out as we intended. For simplicity's sake, the seniority level is a field within the EMPLOYEE table.

To solve this issue, we can utilize a Select (or Switch) case familiar to programmers within the ORDER BY clause. The syntax would look similiar to the following:




...

ORDER BY CASE [Column Name] WHEN [Value1] THEN [Position 1] WHEN [Value2] THEN [Position 2] END

This structure allows us to layout the custom order scheme needed for our solution. Applying this to our sample problem, we end up with a query such as this:




SELECT EMP_ID, NAME, SENIORITY
FROM EMPLOYEES
ORDER BY CASE SENIORITY
WHEN 'SUPERVISOR' THEN 1
WHEN 'ASSOCIATE' THEN 2
WHEN 'EXECUTIVE' THEN 3
END

The result query would then be ordered precisely as required.

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World's first flexible e-paper display heads into mass production

LG on Thursday unveiled the world’s first plastic e-paper display, which the company claims will “revolutionize the E-Book market.” The 6-inch E Ink display features 1,024 x 768-pixel resolution and can bend at an angle of up to 40 degrees. “With the world’s first plastic EPD, LG Display has once again proven its reputation for leadership and innovation with a product we believe will help greatly popularize the E-Book market,” said Mr. Sang Duck Yeo, Head of Operations for LG Display’s Mobile/OLED division. “Based on our success in mass-producing plastic EPD, we are excited as we look toward applying concepts from this experience to future developments like plastic OLED and flexible displays.” The display will be supplied to manufacturing companies in China first, and end-user products could launch in Europe as soon as the beginning of next month. Read on for LG’s press release.

LG Display Begins Mass Production of World’s First Plastic E-Paper Display

With advancements in functionality and design, Plastic EPD to revolutionize E-Book market

Seoul, Korea (March 29, 2012) – LG Display [NYSE: LPL, KRX: 034220], a leading manufacturer of thin-film transistor liquid crystal display, announced today that it has started mass production of the world’s first plastic electronic paper display (EPD) for use in E-Books. The 6″ XGA (1024×768), e-ink, plastic EPD is expected to revolutionize the E-Book market with its advancements in functionality and design.

“With the world’s first plastic EPD, LG Display has once again proven its reputation for leadership and innovation with a product we believe will help greatly popularize the E-Book market,” said Mr. Sang Duck Yeo, Head of Operations for LG Display’s Mobile/OLED division. “Based on our success in mass-producing plastic EPD, we are excited as we look toward applying concepts from this experience to future developments like plastic OLED and flexible displays.”

Innovations in Functionality and Design

The world’s first plastic EPD from LG Display offers users a paper-like reading experience with a plastic substrate that is as slim as cell phone protection film, and a flexible design that allows bending at a range of 40 degrees from the center of the screen. Compared to glass EPD of the same size and resolution, LG Display’s plastic EPD realizes a super slim thickness of 0.7mm which is 1/3 slimmer than existing glass EPD; as well as a weight of 14g which is more than 1/2 lighter.

E-Book users have long expressed a desire for more durable EPD, since around 10% of them have damaged their product screens from accidentally dropping or hitting them. When LG Display’s plastic EPD was put through repeated drop tests, from 1.5m above the ground or the average height of reading when standing, no damage resulted. When put through a break/scratch test involving hitting the display with a small urethane hammer, no scratches or breakage resulted.

As EPD gets thinner, lighter, and more durable with the introduction of plastic EPD, E-Books will be able to offer certain unique benefits compared to smart devices and tablets, including reduced eye fatigue and more efficient electricity consumption in addition to lower prices.

A Manufacturing Breakthrough

LG Display developed a unique technique to utilize the high TFT process, typically employed in general LCD manufacturing and with temperatures exceeding 350 degrees, in the production of its plastic EPD. By overcoming the obstacles associated with applying the existing production process to heat susceptible plastic, LG Display achieved a breakthrough with the successful mass production of plastic EPD able to maintain strong durability in high temperatures.

Availability

The world’s first mass-produced plastic EPD from LG Display will first be supplied to ODM companies in China, followed by completed products to be released in Europe at the beginning of next month.

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Samsung Galaxy S3 display 'will rival the iPhone'

Reports suggest the Samsung Galaxy S3 will come sporting a Super AMOLED HD plus display when it finally launches in the second or third quarter of 2012.

Digitimes spoke to sources in Samsung's supply chain, who revealed the Galaxy S3 is likely to ship with a 4.6-inch screen, boasting a pixel density of 319ppi – quality which will rival the retina display on the iPhone 4S.

In Depth
Samsung Galaxy S3 release date, news and rumours

AMOLED displays provide better power consumption, reaction time, weight and thickness compared to LCD displays, which has lead to predictions that a high number of handsets will use this technology in 2012.

Still no word on a release date

Samsung is the number one producer of AMOLED displays and is looking to introduce into a number of its new models.

The Samsung Galaxy S3 is shaping up to be a stand-out mobile phone, with rumours suggesting it will sport a quad-core processor, large HD screen, 4G, NFC and beefed up camera.

We're yet to hear when the Galaxy S3 will be launched, although Samsung has said it will arrive in the first half of the year.

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Five free cloud storage options

So you just learned that you can store data on something called “the cloud” and access it anywhere in the world so long as you have a smartphone/tablet or a computer with an Internet connection and you don’t need to lug all your important data with you on a portable storage device. 

Well first let’s break the “cloud” bubble for you. Your data isn’t actually stored in thin air, its saved on a server that is hosted by the service provider you are connected with. This data is then accessible by you from any device that is supported by the service provider. All you need is the device and an Internet connection.

If you are looking to back up those important documents, images or music files, cloud storage is an option you should consider. So before you go gung-ho, and drop some cash on purchasing cloud space, here are some free options you may want to check out!

DropBox

Dropbox is a cloud storage service that lets you bring all your photos, docs, and videos anywhere. Any file you save to your Dropbox will automatically be visible on all your computers, phones and even the Dropbox website. You can also share the content with others.

Straight after registration users get 2GB storage absolutely free. You can gain up to 8 GB of additional free storage if you recommend Dropbox to your friends and they start using the service.

If you are in the market to pick up a device from the HTC One lineup (yet to be launched in India), then you are in luck as HTC has announced that users who purchase the device will receive 25GB free Dropbox storage for 2 years. That’s a really good deal considering the fact that 50GB of storage space can be purchased from Dropbox for $9.99 per month.

Apart from your PC/Mac/Linux machine, you can download the DropBox app on iOS, Android, BlackBerry OS and Windows Phone.

You can register for a Dropbox account here.

Box.net (Now box.com)

If 2GB free storage isn’t enough, you can take a look at box.com. This cloud based storage service provider offers 5GB of free storage to users.

If you have an Xperia or LG Android device, you can get 50GB of cloud storage space. This offer is valid until December 31, 2012. 

Apart from storing your data, you can share it as well and receive real time updates to see who has viewed your shared documents.

You can access box.com from your Mac/PC, and from your iOS and Android device as well

You can register for Box.com here.

 

iCloud

Apple too has its fingers in the cloud storage space with iCloud. The service allows users to store data such as music files on Apple’s remote servers for download to multiple devices. The data can be downloaded to your iOS devices, PC/Mac. It also replaces Apple's MobileMe service, acting as a data syncing center for email, contacts, calendars, bookmarks, notes, to-do lists, and other data.

Once you sign up for iCloud, you get 5GB of cloud storage free. If you would like more storage, you will have to pay for it. Apart from being able to store data on the cloud, iCloud lets users wirelessly sync between devices smoothly and seamlessly. Click a picture from your iPhone, and its there on your iPad/Mac. Download an app on one iOS device and it appears on the other.

You can take a look at the features of iCloud here.

SkyDrive

The only service on our list to offer the highest free storage space straight out of the box, SkyDrive gives users 25GB of free personal storage space. The only catch here is that the limit for individual files is 100MB.

To access the service all users need is a Windows Live ID. That’s it. Users can view photos and Office documents that they have stored on SkyDrive from their Smartphone. All users need to do is log on to skydrive.live.com from their smartphones and sign in. Voila! Your data is at your disposal.

If you are a Windows Phone user, the pictures you take from your smartphone can be uploaded directly to SkyDrive automatically, or when you choose. Users can also Create, edit and share Word, Excel, PowerPoint and OneNote documents from SkyDrive

You can sign up for the SkyDrive service here  

Sugar sync

SugarSync gives you online cloud storage for all files — documents, music, photos, and video. If you edit or make changes to files on your PC or Mac, SugarSync automatically syncs your files to the cloud. Apart from the PC/Mac, you can download the Sugar Sync app for iPad, iPhone, Android, BlackBerry, Windows Mobile and Symbian devices.  

Sugar Sync offers users 5GB of free cloud storage.

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Chinese net giant Alibaba testing Pinterest rival

It is a marriage made in heaven for shopping addicts. Social shopping, the merger of social networking and e-commerce which has hooked millions of users in the United States, has now captured the attention of China's internet giant. 

Alibaba Group's social shopping platform Fa Xian (http://faxian.etao.com), launched on a testing basis four weeks ago, is already luring 60,000 viewers a day. 

"Over the long run, social commerce in China has the potential to be bigger than the United States," said Hans Tung, managing director of venture capital firm Qiming Ventures. 

Social shopping websites allow users to post photos of items on virtual pin boards, which others can comment on. Some sites allow users to purchase some of the items by clicking on the photos. 

The business model originated in the United States in the mid 2000s when firms such as Kaboodle first set up shops. Others have emerged since then, including Fab.com and most recently Pinterest. 

In China, the home of world's largest Internet population with nearly half a billion users, social shopping websites, such as Mogujie, LinkChic and Xinxian, have been launched over the past year. 

Alibaba, 40 per cent owned by Yahoo Inc, is looking to incorporate these rivals into Fa Xian, which means discovery in Chinese. Unlike other US social shopping websites, all the items on Fa Xian can be purchased through its two e-commerce websites, Taobao Mall and Taobao Marketplace. 

"We have about 10 partners right now. At the end of the year, I hope to see if we can achieve 100 partners, because this year China's social shopping industry is very hot," Chen Lijuan, director at eTao, Alibaba's search unit that operates Fa Xian, 

Fa Xian also plans to expand to include other e-commerce vendors outside the Taobao ecosystem, such as Jingdong Mall. 

Cao Xiaolei, a 30-year-old office worker who has been using Mogujie since last July, said she can spend up to an hour looking through the website for items she likes. 

"The products on the website have been selected and that can save me time and give me inspiration," she said.

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Google Is Now a Graphing Calculator

Google has decided to make its simple search box into yet another thing. It's now a WebGL-powered 3D graphing calculator. If you type in a two-variable function, Google's search box on the desktop will graph an animated, interactive, 3D plot right in your browser.

Google is moving increasingly toward providing answers when they're faster than Web results. But putting an advanced graphing calculator into search is an obvious defense against Wolfram Alpha, which is notably Apple's Siri partner for math and science questions. Google search is fighting a two-front war, with Facebook and social search on the other side. How many things can Google search be at once?

Google has had Universal Search for five years, but the landscape has shifted drastically. When Google added images, videos, maps and places to search results, it only secured its dominance over those verticals. Google's competitors freaked out, but Google pressed ahead.

This ill will is coming back to bite Google now. Yelp, the highest-profile company that objected to Google's Universal Search practices, is now going public and hitching its wagon to Apple. When iPhone 4S users use Siri to search for a restaurant or gas station, it will bypass Google altogether and use Yelp.

Likewise, Siri uses Wolfram Alpha for math and science questions. It's a 'computational knowledge engine' built on the theories and proprietary programming language of Stephen Wolfram. Graphing isn't just built into it; it's a primitive concept of the language underlying it. Can Google compete with that?

Well, not until WebGL works on phones. But at least on the desktop, Google is still devoted to the idea of using search as a starting point for everything on the Web. It's contending with Wolfram Alpha on the side of computed answers, and it has Facebook's dominant social graph on the other side in personalized search. Facebook is reportedly building new search technology, too.

Time will tell whether the convenience of having all these disparate services in one place will win out, or whether Google's notion of search will be stretched too thin.

The new graphing capabilities work internationally on modern desktop browsers like Chrome and Firefox, as well as Safari, which Google's blog post unsurprisingly neglected to mention - if, that is, you don't have a 'low-end' system like the most recent MacBook Air.

You can try it out by pasting this function into Google on your desktop:

sqrt(cos(3*x))*cos(100*y)+1.5*sqrt(abs(x)) + 0.8 x is from -1 to 1, y is from -1 to 1, z is from 0.01 to 2.5

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15 best graphics cards in the world today: Updated

Best graphics cards: Overview

What graphics card should you buy? Our 15 best graphics cards in the world article is regularly updated.

PC gaming is currently going from strength to strength. Upcoming games such as Bioshock Infinite and The Darkness II look set to raise the graphical bar even higher, and recent games look phenomenal on the PC. Just compare Skyrim running on a decent PC and graphics card to it running on an Xbox 360 or PlayStation 3 and the difference is like night and day. Plus as the consoles stagnate due to their ageing technology, it's something that's only set to continue.

In order to experience such games at their best, though, you're going to need to ensure you have a machine that's up to the task. And by machine, we're primarily focusing on your graphics card.

So welcome to our best graphics card article – it's constantly updated with the very latest best graphics cards.

It's the graphics card that does the serious work when it comes to rendering your games, and the more effects and higher resolutions you throw at it, the more is asked of that graphics card.

It's important to pick your graphics card so that it works well with your display, or displays. There's no point, for instance, trying to power a 30-inch screen with the likes of a GeForce GTS 450.

By the same notion, running a standard 20-inch screen with the likes of an AMD Radeon HD 6990 won't begin to tap into the card's power.

As a quick rule of thumb, whatever you spent on your screen, you're going to want to spend a similar amount to power it. Roughly.

The question is, which one of the many graphics cards out there should you actually spend your hard earned cash on? Here TechRadar highlights the top 15 cards worth considering. We cover the notable cards from the last generation, the best all-rounders for most PC gamers and the £550 monsters that can handle multi-screen outputs.

In this guide we'll let you know what's hot, what's cool and what are the fastest GPUs available right now and worthy of your time.

Best of all, because we're now enjoying the second generation of DirectX 11 hardware, every card we look at here is capable of rendering the latest, funkiest DirectX 11 games.

So how does your graphics card stand in our countdown, and is it time for an upgrade?

Graphics card glossary

There are a lot of terms and acronyms that get bandied around when talking about graphics cards, and not a lot of explanation to go along with them.

Before we delve into the meat of the feature let's take a minute to clear things up a little.

GPU – This is the graphics processing unit, the chip at the heart of the graphics card. Many cards use the same GPU but partner it with different components and at different clockspeeds to produce slower or faster graphics cards.

GDDR – Graphics Double Data Rate memory is the specific kind of memory that is used on graphics cards.

ROPs – The Render Output unit comes into play during the final stages in the rendering process, bringing together the data from each of the memory buffers in the graphics card's local memory. The more of them you have, the better off you are.

CUDA – Compute Unified Device Architecture is a coding language Nvidia invented to allow parallel computing on its range of GPUs. From its 8 series upwards all its cards can use CUDA to speed up parallel processing applications, such as video encoding, faster than your computer's CPU.

PhysX – Originally an accelerator chip and software layer from the small company Ageia, Nvidia bought up PhysX and has now applied it to its GPUs, again from the 8 series forward. It allows for more advanced physics simulations, such as liquid or cloth, in games that have been coded with the PhysX software included.

Crossfire and SLI – These are the relevant multi-GPU configurations from both AMD and Nvidia. Both allow multiple graphics cards to be connected together to increase the rendering performance. Historically this has been fraught with driver issues and diminishing returns for the extra cards, but as the latest cards have been released we are getting closer to doubling the performance by adding in a second card.

PCB – The Printed Circuit Board is the physical board that graphics cards (and all other micro-electronics) have their components attached to. The boards are printed with conductive pathways between the relevant components instead of using physical wires.

DirectX – Microsoft's DirectX is a collection of its own proprietary APIs (application programming interfaces) for dealing with multimedia tasks on its own operating systems. The Direct3D part is specifically to do with 3D graphics and utilises hardware acceleration if there is a GPU in place to take advantage of it.

Tesselation – This is one of the key buzzwords to come from Microsoft's latest graphical API, DirectX 11. It's designed to add extra geometry to a simple polygon, using displacement maps to tell the GPU where to raise and lower parts of the polygon as the graphics card computes the data. The idea is to add geometry to objects in a game world without significantly impairing performance. It's set to become a key battleground in the graphics war in the coming years.

The best budget graphics cards

Getting great gaming performance doesn't have to involve breaking the bank. Here are the best budget graphics cards.

5. AMD Radeon HD 7750 - £80

The AMD Radeon HD 7750 launched at the right side of £80, making it an altogether friendlier proposal than the AMD Radeon 7970 which goes for around £440. These new-gen AMD cards boast some excellent power efficiency by shutting off all but one core when your system enters power save mode.

But what's this HD 7750 missing out on to hit that price point? The HD 7750 is quicker than its big Nvidia rival, the GTX 550 Ti, and its predecessor, the HD 5770 - but not the HD 6770. General performance is limited primarily by a slender 128-bit frame buffer, however the die-shrink down from 45nm to 28nm and increase in transistor count that comes with it gives this Southern Islands card a definite edge in tessellation-heavy tasks. You can also eke out some modest improvements through overclocking, with big core and memory clock increases running smoothly and without crashes - we had ours cranked up to 900 MHz on the core clock from the 800 MHz stock setting without any glitching or hangs.

Read our AMD Radeon HD 7750 review

4. AMD Radeon HD 6670 - £59

It's all very well talking about £600 graphics cards that need PC cases the size of Andre the Giant to house them, and a mini Arc reactor to keep them powered, but how many of us are actually going to drop a month's wages on such a pixel-pushing behemoth? More likely you're going to be looking at a maximum outlay of around £150-£200.

And currently there's a lot of graphics processing power available all the way down the price spectrum too. AMD though has come in, GPUs-blazing, at a sub-£100 price point with a DirectX 11 graphics card, the Radeon HD 6670.

At under £70, it's a decent compromise between price and performance, and if you're really on a tight budget you'll still be able to game at your 22-inch panel's native res, albeit with a few graphical niceties dialled down.

As ever in this tightly compressed graphics card market there's a more powerful alternative, but it's a few pounds away. For less than a tenner you're looking at XFX's single-slot Radeon HD 5770 (http://www.techradar.com/reviews/pc-mac/pc-components/graphics-cards/xfx-radeon-hd-5770-926213/review), and that's rather close to being a bone fide gaming GPU.

Read our Sapphire AMD Radeon HD 6670 review
Read our HIS 6670 Fan 1GB GDDR5 review

3. Nvidia GeForce GTS 450 - £81

The Nvidia GeForce GTS 450 is in serious gamers' graphics card territory, without hitting the big prices.

Nvidia doesn't have a great lineup in the budget segment of cards, and anything lower than this here GeForce GTS 450 isn't really worth a look for those with any passing interest in frame rates. This venerable card does have some gaming chops to offer, and for the £81 cost it's a tough card to argue against.

Immediately you can feel the step up in performance terms with this gaming-oriented card. With DiRT 3 and Far Cry 2 we saw the card hit 32fps and 52fps respectively, and that's with 4x AA running at very playable speeds. You could drop this into any system and be hitting gaming speeds across most modern titles at the modest 1680 x 1050 resolution. Should you not mind taking the performance hit, this card will also give you access to PhysX extras in game and 3D Vision, if you so wish.

Read our Nvidia GeForce GTS 450 review
Read our MSI GeForce GTS 450 Cyclone review
Read our Asus GeForce GTS 450 TOP review

2. AMD Radeon HD 6850 - £118

To be honest we were rather unforgiving of the HD 6850, at launch it was pricing itself almost out of the market.

It was going toe-to-toe with Nvidia's 1GB GTX 460 which, at the time, just about had it pipped in performance terms. It was also a little pricier than the GTX 460, coming in around the £160 mark.

Again though time has been kind to the HD 6850. The price has dropped a huge amount, indeed AMD recently announced a further price-drop bringing the card down to less than £120, which for a spec like this is a serious bargain.

AMD's constant driver updates too have meant that performance has increased over time as well. The Barts Pro GPU core at the heart of the HD 6850 is a reworking of the Cypress Pro that made the HD 5850 such an impressive card back in the day. It doesn't have the huge number of Radeon Cores the HD 5850 had, but still maintains the ROPs count of 32.

Read our XFX HD 6850 review
Read our Sapphire Radeon HD 6850 review
Read our HIS Radeon HD 6850 review

1. AMD Radeon HD 5770 - £100

For budget-conscious gamers, the HD 5770 should be a serious consideration. Have a scout around the online retailers, and you'll see that examples can be had for less than £100 now.

Offering competent performance at the mainstream 22-inch resolution of 1680 x 1050, it also comes with the promise of cool-running, quiet operation – a trademark of AMD's last-gen design philosophy.

However, try to crank the shinier graphical elements – such as Anti-Aliasing and Anisotropic Filtering – too high, and the card starts to run out of grunt.

AMD's EyeFinity technology, which enables multi-screen scaling, is a very real option with the 5770, although we wouldn't recommend the 5770 for multi-screen gaming; it just doesn't have the throughput for gaming at huge resolutions.

The really interesting thing about the HD 5770 is what its price represents. At these low prices, our thoughts turn to CrossFire setups. For under £200, you can net yourself a twin-card setup that offers kick-ass performance at mid-range resolutions.

If you're content with that 22-inch monitor and want zingy performance on a budget, this CF setup is probably the cheapest way to achieve it... Oh, and did we mention the 5770 is DX11 capable? Yum.

Read our XFX Radeon HD 5770 review
Read our Gigabyte HD 5770 Silent Cell review

Best mid-range graphics cards

These mid-range graphics cards represent the sensible money for most PC gamers – combining great raw performance with a price tag that won't make you pass out.

If you're looking to power a screen with a native resolution of 1680 x 1050 or 1920 x 1080, then you really don't need to get anything more powerful than this. At least given the current slew of games.

These cards also hold an ace up their sleeve if you have an SLI or CrossFire motherboard in your rig, because they enable you to boost the performance of your machine by adding in a second card as your needs progress.

5. Nvidia GeForce GTX 550 Ti - £128

Originally designed to replace the GTS 450, the GTX 550 Ti has recently found itself being pushed out of the frame by the Radeon HD 6790 (which we're looking at next). Yes, it's a next-generation graphics card, but is that alone enough to make it relevant? Not really.

As with the Radeon HD 6790, The Nvidia GeForce GTX 550 Ti suffers comparison with the slower, but more-affordable GTS 450 and the faster, and only a bit more pricey GeForce GTX 460. Indeed it's testament to the GTX 460 that it still manages to define this end of the market.

If you've got a 20-inch or 22-inch screen, then the GTX 550 Ti is briefly worth considering, because it will produce playable frame rates at 1680 x 1050 at reasonable settings.

Unfortunately, unless there's a bizarre disease that specifically targets the GTX 460 and removes it from the world, we'd recommend hunting down that older card every time.

Read our Zotac GeForce GTX 550 Ti AMP! review
Read our EVGA GTX 550 Ti SC review

4. Asus EAH 6770 DC - £118

Asus has released the highest-clocked passively-cooled graphics card around in this, the Asus EAH 6770 DC.

And it's whisper quiet too.

There was a time, not too long ago, when if you wanted to build a silent or very quiet PC you knew you were going to have to sacrifice any notion of serious gameplay to get the quietness needed for the system you were building.

Well, helping to kick that idea out of touch, Asus has introduced the EAH6770 DC SL/2DI/1GD5. A really snappy name to remember that mouthful is. The card combines AMD's HD6770 core with, it must be said, a pretty massive passive heatsink and cooling array.

It's created a passive card that makes a pretty good fist of playing today's demanding games even at high resolutions.

Although size-wise it's not a card for the more compact of PC cases.

Read our Asus EAH 6770 DC review

3. AMD Radeon HD 7850 - £190

The HD 7850 pretty much finalises AMD's current plans for the Southern Islands line up, bar the crazy-expensive dual-GPU New Zealand card which is likely waiting on Nvidia's new cards.

The AMD Radeon HD 7850 is also the card that's arguably got the most chance of being successful out of this family. At the price it looks likely to retail at, the sub-£200 mark, it could well be the highest-selling of AMD's mid-range cards.

The fact AMD has filled out these lower-caste cards with all the same features as their higher-end brethren is refreshing, as is the fact that we'll get all the HD 7850 goodness in such small footprints as 7.8-inches.

Again, it's the same Graphics Core Next story – the overclocking headroom is immense. The OC path is the only way to get the most out of these cards

Read our AMD Radeon HD 7850 review

2. Nvidia GeForce GTX 560 Ti - £154

The GTX 560 Ti is essentially the direct replacement for the awesome GTX 460.

Though that's not actually how it's running. The performance of the GTX 560 Ti actually means it's retiring the GTX 470 with the GTX 570 effectively retiring the GTX 480 and the GTX 580 just standing on it's own. In competition terms the GTX 560 Ti is being pitched directly against AMD's sub-£200 Radeon HD 6870, but is also touted by Nvidia as something that can also take on AMD's Cayman-powered Radeon HD 6950.

The GTX 560 Ti hits Nvidia's marketing claims of 30% better performance over the GTX 460 and isn't asking any more for it than it did for the previous generation.

The impressive overclocking capabilities of the card are also worth special mention, especially considering the card is recommended to come in below the £200 mark.

Read our Gigabyte GTX 560 OC Edition review
Read our EVGA GTX 560 Ti DS review
Read our Zotac GTX 560 AMP! Edition review

1. AMD Radeon HD 6950 - £210

Every few years a graphics card is released that sums up that generation better than any other. We're talking about the likes of the 8800GT and the budget-focused Radeon X1950 Pro. Cards that transcend their immediate markets and time frames and stand up for years to come as being bang on the money.

The AMD Radeon HD 6950 defines the market. Cheaper cards look up to it for its raw power, while the top-end cards are mindful of the sheer value it offers and are rightly fearful of what can be achieved when two are cajoled together in CrossFire.

The Radeon HD 6950 isn't a subtle reworking of the first generation of DX11 graphics in the same way that Barts is, but rather a complete reworking of the inner logic of AMD's graphics chips. And it's an incredible card for it.

The performance is incredible, at console-breaking 1080p resolutions, and in DX11 games it punches well above its weight. If you're looking for a no-nonsense card that will last you until DX12 rolls out, and don't plan on running insanely high resolutions, this is the card for you.

Those with the stomach for it will discover that they can turn their £200 Radeon HD 6950 into a fully fledged 6970 with a BIOS flash as well. Here's a card that both AMD and Nvidia are going to be hard pushed to beat any time soon. It's simply incredible.

Read our AMD Radeon HD 6950 review
Read our MSI Radeon HD 6950 Twin FrozR II review
Read our Sapphire Radeon HD 6950 Dirt 3 Edition review
Read our Sapphire Radeon HD 6950 2GB review

The top graphics cards in the world today

The following five cards represent the pinnacle of modern graphics performance. These are cards that are beyond the sweet spot of what's needed in order to enjoy the latest games at reasonable resolutions.

The following cards are essentially here to fill the niches in gamers' requirements that the likes of the AMD Radeon HD 6950 can't satisfy. Here we're talking about outputting to 27-inch and 30-inch panels that have a native resolution of 2560 x 1600. Or multiple screen displays made up of three or more 22-inch or 24-inch panels.

This end of the market is complicated somewhat by the advances made in SLI and CrossFire. These twin-graphics card pairing technologies now genuinely provide the performance improvements over single cards that you would hope for – 90-95% is often the norm.

A pair of cheaper cards in SLI can outperform the following cards too, which means the requirement of having a supporting motherboard is generally the only thing holding you back.

5. Nvidia GeForce GTX 570 - £280

Value for money may seem like a strange metric to pull out of the hat at this end of the graphics market, but the GTX 570 does a decent turn at making your investment feel prudent rather than simply excessive.

Essentially a replacement for the soon to be retired GTX 480, here's a card that does everything that Nvidia's last-generation top dog did, but without the problems that card suffered from when it shipped.

The cooler is quiet and more efficient, and the raw power on offer from this sub-£300 card is stunning. This is a slightly cut down version of the GTX 580, losing one Streaming Multiprocessor (or 32 CUDA cores, to put it another way) and 8 ROPs.

The GTX 570's core operates at 732MHz as opposed to the GTX 580's 772MHz, while the 1,280MB of GGDR5 memory speeds along at 950MHz, as opposed to the GTX 580's 1,002MHz.

For the money, there isn't a lot out there that can touch the GTX 570 in terms of pure performance, apart from possibly a pair of GTX 460s in SLI – but such a configuration requires an SLI motherboard.

Read our Nvidia GeForce GTX 570 review
Read our Zotac GeForce GTX 570 review

4. AMD Radeon HD 7970 - £450

AMD blinked first and opted to release its brand new graphics card architecture before Nvidia did. It was a brave move by AMD though. Bringing out a radically different graphics design spec, compared with its previous vector processors, in the same year as it brought us a brand new CPU architecture.

It may well be one of the fastest single-GPU cards around at the moment, but there is still little justification for the price. There are very few of us out there running a monitor capable of the eye-watering resolutions of 2560x1600 so realistically a 1920x1080 resolution is going to be more likely.

And at that resolution the excellent £365 Nvidia GTX 580 is all the card you're going to need. The overclocking potential of the AMD Radeon HD 7970 is incredible.

Topping 1,100MHz is a huge overclock and makes it almost comparable to the previous generation of dual-GPU cards.

Read our AMD Radeon HD 7970 review
Read our Sapphire Radeon HD 7950 OverClock Edition review

3. Nvidia GeForce GTX 580 - £395

Created as the spiritual successor to the much-maligned GTX 480 (http://www.techradar.com/reviews/pc-mac/pc-components/graphics-cards/nvidia-geforce-gtx-480-679629/review), Nvidia took the problems it had with its first DX11 graphics card and corrected them with the GTX 580.

This means you get a full-fat core boasting 512 CUDA cores and 48 ROPS, not one that has been cut down to achieve better yields. And all running at a healthy 772MHz with a 1,002MHz memory bus for the 1,384MB of GDDR5 memory.

Not everyone needs the power of a GTX 580 – only those with serious screens to power. This is a market targeted by the twin-GPU Goliaths that are the AMD Radeon HD 6990 and Nvidia's own GeForce GTX 590.

The GTX 580 still has the nod, however, because those cards have had to be throttled back to fit on a single card, while here you know nothing is being constrained. This is still the most sensible option for anyone looking for unfettered speed from a single GPU.

Read our Nvidia GeForce GTX 580 review
Read our Zotac GeForce GTX 580 AMP! review
Read our EVGA GTX 580 Hydro Copper 2 review
Read our MSI GTX 580 Lightning Twin Frozr III review

2. AMD Radeon HD 7950

AMD is really putting the pressure on Nvidia now with its second release of the new AMD HD 7000 graphics card generation, the AMD Radeon HD 7950. We've been pushing the Nvidia GeForce GTX 580 as the go-to gamer's card since it was released, but the HD 7950 has that beat and for a good chunk of cash less than the Nvidia card.

And that's just at stock speeds. When you start overclocking this card the difference in performance increases hugely.The AMD HD 7950 could also be a massive hit for the CrossFire crew too, as for £700 you'll find yourself with an insanely quick graphics setup.

And for £300 less than an equivalent HD 7970 array. The AMD Radeon HD 7950 is one hell of an impressive pixel-pusher, and Nvidia is going to have to work incredibly hard with its Kepler cards to best this excellent card.

Read our AMD Radeon HD 7950 review
Read our Sapphire Radeon HD 7950 OverClock Edition review

1. Nvidia GeForce GTX 680 - £410

It may have been a long while coming but the Nvidia GeForce GTX 680 is on the way to balance up the next-generation graphics market.

AMD launched its Radeon HD 7970 in December so it's a bit of gap that Nvidia has to make up with its latest top-end GPU.

The Nvidia GeForce GTX 680 is its latest £400-odd, top-of-the-line card and is now the fastest graphics card in the world. We all kind of knew that would be the case, after all Nvidia has played the waiting game with AMD, letting the competition draw first and release its entire slew of HD 7000 graphics cards.

That meant Nvidia could see how the competition was performing and ensure its engineers finalised the GTX 680 specs and set the clocks to ensure the requisite 10% performance improvement.

As it turns out this Kepler-based Nvidia GeForce GTX 680 is far more than just another big, power-hungry graphics card, relying on pure grunt alone to give it the edge.

This is actually a far more elegant card than people might give it credit for.

It's not the power-crazed GPU behemoths we're used to from Nvidia, but it's still got the performance chops and some neat extra tricks.

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