shared graphics vs dedicated graphics

When you buy a computer, more specifically a laptop, the one piece of hardware that is the most difficult to choose is the graphics card. You may have heard terms like integrated, discrete and dedicated. First off, to erase some confusion, discrete and dedicated mean the same thing, so there are only two terms you need to know to understand the difference between the two kinds of graphics cards. So what is the difference between an integrated and dedicated graphics card, and what are the benefits and disadvantages of each? The answer to the second question depends on what you need your computer to do. Before you buy a gaming laptop or a graphics card, you need to know how you will use it. To help you decide what you need, here are the differences between integrated and dedicated graphics cards.
Integrated
An integrated graphics processing unit (GPU) doesn't use its own RAM; it utilizes the system's memory instead. So, if you have a computer with 4GB of RAM, the video card can use anywhere between one and five percent of the available memory for graphics processing. Of course, this percentage varies depending on the size of task, especially if you're multitasking or playing a game.
The benefit to an integrated unit is that it is cheaper, which in turn means a less expensive computer. An integrated graphics card also generates much less heat than a dedicated video card and uses drastically less power, which improves the overall battery life. Integrated graphics cards are perfect for people doing everyday graphics processing. This includes watching or editing videos, 2D gaming and general word processing. Such activities aren't graphic intensive, so a low-end video card is ideal. That doesn't mean you won't be able to play 3D games, but you will have to turn down the graphics settings or you'll experience in-game slowdowns.
Dedicated
A dedicated, or discrete, GPU has its own independent source of video memory, leaving the RAM your system uses untouched. If you have a GeForce GTX 680M video card with 2GB of video memory, for example, that memory is completely separate from your computer's 8GB of system memory. Dedicated cards are perfect if you are into serious gaming or are a professional graphic designer.
There are a few drawbacks to having a dedicated card, however. If you don't have the appropriate design or a good fan, these video cards will get warm. If you are a serious gamer or if you run a dual-monitor system, the GPU will have to work harder and will heat up quickly. These cards are also power hungry, so using a laptop with dedicated graphics card will decrease the battery life. You should also expect to pay more for this kind of card. Price differences can vary, up to hundreds of dollars more for a dedicated GPU than an integrated GPU.
One thing we recommend if you are going to use a dedicated card is to make sure you get a laptop with at least one or two fans and plenty of vents. You can find special cooling stands as well if you want give your system extra protection from heat.
Some video cards are switchable. This means the GPU is built as a dedicated and integrated card. When you do things such as editing a spreadsheet or browse, the card switches to the integrated unit, which will preserve the battery of your laptop. When you watch a high-definition movie or play a graphic-heavy game, the card then powers up and works as a dedicated card, improving the overall performance but lowering the battery life.
Before you make a decision regarding the kind of graphics card you want, be sure you know how you will use it. If you are a casual user, integrated graphics are great. You can browse the web, watch YouTube videos and even watch Blue-ray movies without any problems. Dedicated video cards are perfect for those of you who want the best visual experience, whether you are gaming or designing graphics. Remember, games' visual designs will continue to improve. You should plan ahead and find a card that will hold up for at least a few years before you need to upgrade.

AMD vs Nvidia: who makes the best graphics cards?

Mac vs PC. Microsoft vs Google. Intel vs AMD. There's no shortage of monumental rivalries in the tech industry. But the royal rumble between ATI and Nvidia for dominance of 3D graphics is one of the roughest of the lot.
The contest is really AMD vs Nvidia. After all, AMD snapped up Canadian graphics outfit ATI back in 2006.
More importantly, however you slice it the histories of ATI and Nvidia have been very closely intertwined. Both started out as specialists in PC graphics and have since branched out into non-PC platforms such as games consoles, mobile devices and set-top boxes.
More recently, ATI's acquisition by AMD seems to have set it on a very different path for the future from Nvidia. But let's start by reminiscing on a few of our favourite ATI vs Nvidia fisticuffs from yesteryear before taking a look at their current offerings.

AMD vs Nvidia: RIVA and Rage
The early days of graphics on the PC saw 3D cards like Nvidia's RIVA 128 and TNT2 take on ATI's Rage and Rage 128. But it was Nvidia who presaged the modern GPU or Graphics Processing Unit with the mighty GeForce 256 in 1999. It was the first graphics chip with hardware transform and lighting capabilities. And it was fast. Damned fast.
ATI responded in 2000 with the Radeon graphics card. Ever since, successive generations of GeForce and Radeon GPUs have been leapfrogging each other in the race for graphics supremacy. Nvidia had the early advantage with the GeForce, GeForce 2, GeForce 3 and GeForce 4 series arguably having the edge over ATI's Radeon, Radeon 7500 and Radeon 8500.

But in 2002 ATI turned the tables with the awesome Radeon 9700 Pro. The first GPU with fully programmable shaders, the 9700 Pro was massively more powerful than any graphics chip before. It took until early 2003 for Nvidia to respond with the ill-fated GeForce 5800 Ultra, a GPU that never lived up to expectations.
Nvidia was back on form a year later with the GeForce 6800 series. A tit for tat ensued with neither ATI nor Nvidia achieving a clear advantage. It was during this period that Nvidia introduced its revolutionary multi-GPU SLI technology and ATI responded with the copycat Crossfire platform. There really was nothing to separate them.

AMD vs Nvidia: Radeon rethink

At least, there wasn't until ATI released the underperforming Radeon HD 2900 XT. Like Nvidia's calamitous GeForce FX series, the 2900 arrived late, ran hot, underperformed and couldn't match its opposition, the GeForce 8800 Ultra.
But unlike the GeForce FX, it lead to a fundamental strategic rethink. AMD decided that in future ATI would no longer chase ultimate performance with its top GPU. Instead it would aim for maximum bang for buck and introduce dual-GPU boards to cater for enthusiasts demanding ultra-high performance.
The culmination of this rethink was the Radeon HD 4870. Launched in mid 2008, it was half the price of Nvidia's competing GeForce GTX 280 but delivered at least 80 per cent of the performance. It was a winning combination.

AMD vs Nvidia: The DX11 era
Of course, graphics technology waits for no man and much has changed since the Radeon HD 4000 series and GeForce GTX 200 hit the market in 2008. Late last year AMD unleashed the Radeon HD 5000 series, the world's first family of graphics chips with support for the latest DirectX 11 multimedia API from Microsoft, as seen in Windows 7 but also available as an update for Windows Vista.
It took a little longer for Nvidia to respond in kind with the GeForce GTX 400 family. It eventually turned up earlier this year and since then its been these two pixel pumping graphics architectures fighting it out for top DX11 honours.
Topping the current single-GPU tables, therefore, are the ATI Radeon HD 5870 and Nvidia Geforce GTX 480. Thanks to AMD's greater emphasis on value, the GTX 480 weighs in around £100 more expensive at £430 or so.
For the money Nvidia gives you an extra billion transistors for a faintly ridiculous total of three billion. You also get a little more memory as standard, 1.5GB to the 5870's 1GB. However, it's worth noting that 2GB variants of the 5870 are now available for less than the 1.5GB GTX 480.
Anyway, what you don't get from the 480 is a huge performance advantage. Yes it's a little quicker than the 5870. But not nearly as much as it needs to be given the extra cost and complexity.

AMD vs Nvidia: Cut-down cards

It's a similar story further at the next rung down the graphics ladder. Both AMD and Nvidia offer slightly cut down versions of their top GPUs. The Radeon HD 5850 is yours for £225 and retains 1,440 of the 5870's 1,600 stream shaders. Meanwhile, Nvidia's GeForce GTX 470 weighs in around £295 and packs 448 of Nvidia's mighty CUDA cores. The GTX 480, for the record, has 480 cores.
Once again, the 470 is a little quicker than its AMD equivalent, but it's also much more expensive. From there, things get a little more complicated. AMD does a silly-money dual-GPU Radeon HD 5000 board, the 5970. In most tests of pixel pumping prowess, it's the quickest thing out there (NVIDIA has yet to wheel out a dual-GPU take on the GTX 400 series). But just occasionally its dual-GPU architecture and split-memory set up gets the better of it.
Move into mid-range territory and direct comparisons between ATI and Nvidia are currently a bit tricky. That's because Nvidia has yet to release more affordable chips based on Fermi, the new DX11 architecture that underpins the GTX 480 and 470 GPUs.
Consequently, the Radeon HD 5770 (£125), Radeon HD 5670 (£85) and Radeon HD 5570 (£72) are lording it without any DX11 competition.
Instead, Nvidia makes do with older chipsets based on DX10 tech, such as the GeForce GTS 250 (£125) and GeForce GT 240 (£72).

Advantage Nvidia?
That said, Nvidia has recently released an even more cut-down version of the Fermi chip in the new GeForce GTX 465, on sale now from around £230. But what it really needs is some pukka mid-range DX11 chips to take the fight to AMD. And it needs them soon. AMD has already released its family of second-generation DirectX 11 GPUs.
Read ourAMD Radeon HD 6870 review
In the meantime, it's not all bad news for Nvidia. Arguably, it has an edge in at least one important DX11 feature, the hardware tessellator. Designed to spew out huge numbers of polygons and therefore give games more geometric detail and realism than ever before, the tessellator could prove to be the killer feature in DX11. Early tests suggest Nvidia's chips have more tessellation power than ATI's.
Nvidia is also way ahead of ATI when it comes to stereoscopic 3D. Nvidia's 3D Vision technology is the best way to get 3D on your PC today. It works with a large number of games and is also compatible with certain formats of 3D movies including Blu-ray 3D. But like most other 3D display technologies, wearing a pair of geeky goggles is the price of participation.

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