If you're looking to upgrade your PC in time for Christmas, or build a new rig based on Nehalem, one of the most fundamentally important choices you make will be the graphics card.
Choose wisely, and you'll have years of high definition gaming ahead of you.
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Choose badly and you'll be back to the shops by June.
But which offer the best performance in their category, and which are good value buys? Here's TechRadar's pick of the five best:
Asus Radeon HD4870 X2 £400 www.asus.com
The title of 'Fastest graphics card in the world' is a bit of a misnomer, really. The X2 suffix indicates that this AMD card actually has two processors on board, which means it works in the same way as a CrossFire X or SLI setup, just without taking up an extra PCI-E slot.
On the one hand, it delivers earth-shattering performance that can't be rivalled by any one GPU. On the other, it raises concerns about driver support. The latest driver from AMD seems to be working well in most games, but there's no guarantee that all will be well in the big Christmas line up. The dual processors also make it blisteringly hot and power hungry to run.
Still, if you want the best, this is it. If you don't have a 30-inch monitor that requires the kind of pixel power it puts out, though, you might want to look elsewhere.
Sapphire HD4850 X2 £317, www.sapphiretech.com
A similar principle has been applied here. Two of AMD's HD4850 chips have been soldered onto a single circuit board and attached to a ruddy great heatsink for 'CrossFire on one card'.
Performance is reported to be more or less the same as Nvidia's top ranking GeForce GTX280, and having seen HD4850s in CrossFire configurations before, TechRadar is not surprised in the least.
Again, though, any multi-GPU configuration gives us cause for concern when it comes to driver support. There's nothing worse than booting up your favourite game on its day of release and having to drop the resolution because you can only run one GPU.
On the other hand, it does look like it's a few pounds cheaper than a GTX 280, so is a very tempting one for loyal AMD fans.
BFG GTX 280 H2OC £446 www.bfgtechnologies.com
The glory of 'Fastest single chip' then, goes to Nvidia's GeForce GTX 280. Armed with 240 stream processors and an enormous 1GB of memory on a 512-bit bus, it's a huge card with bigger aspirations.
That's not enough for everyone, though. This BFG model is overclocked by almost a fifth to 680MHz and kitted out with a bespoke water-cooling block. It adds about £130 to the price of a regular GTX 280, but will certainly find a home in a specialist water-cooled system. The rest of us would be better off buying a vanilla version for the reduced price.
Gigabyte GeForce GTX 260 OC approx £220, www.giga-byte.co.uk
The problem with the highest end cards is that game engines really aren't keeping up with graphics hardware. Unless you're running a 24-inch monitor or above with a native resolution of 1,920x1,200 or higher, you really don't need to spend a fortune on a top-end videocard. You'll just be pumping out more frames than the eye can see.
Move down to the £200 range, and Nvidia's newest GPU tops the tables. There are two versions of the GTX 260 – one with 192 stream processors on board and one with 216 – and they can be hard to tell apart. This is one of the latter, and the extra power it gains over the lower end model is enough to make it almost as fast as a GTX 280 for two thirds of the price.
HIS Radeon HD4850 IceQ 4 £131, www.hisdigital.com
The real action, though, is at this sort of price level. That's what most people spend, and that's where there's a glut of cards all with similar levels of performance. There's the Radeon HD4830, for example, or the GeForce 9800GTX to choose from.
Our current favourite entry into this category at the moment is this overclocked version of AMD's HD4850 – itself a very good card. HIS has fitted an almost silent heatsink with a very capable fan. This means it can be shipped running at higher clockspeeds than a stock version of the card, and the result just edges it to the top of the table for hardware at this price.
Now read TechRadar's The ultimate guide to graphics cards.