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ATI Radeon HD 3850 - first benchmarks!

We test ATI's new mid-range graphics chip on Crysis, Unreal Tournament 3, Company of Heroes and a whole load of other games. At £110, is this the bargain of the year?

ATI Radeon HD 3850

Much like the number 13, the number 666 (for it is a human number) has so far been avoided by the PC business. We’ve had some close run-ins when Intel released its 667MHz Celeron, and 667MHz DDR memory came out, but now ATI has hit the number spot-on with the new Radeon HD 3800 GPUs, which it proudly claims have a beastly count of 666 million transistors.
What’s more impressive about this mighty transistor count, though, is that all these transistors have been squeezed into a die that measures just 192mm2. By comparison, ATI’s previous top-end card, the Radeon HD 2900XT had 700 million transistors in a 408mm2 die – over twice the size. This is all because ATI has moved to a much smaller 55nm manufacturing process, making it the first 55nm GPU, ever.

This is good for a number of reasons. For a start, smaller transistors require less power, and this is demonstrated by the fact that the Radeon HD 3800 cards only have a single six-pin PCI-E power connector, as opposed to the six-pin and eight-pin connectors found on the Radeon HD 2900 cards. In fact, ATI claims that the Radeon HD 3800 cards will consume ‘less than half the power draw of the 2900,’ and the 3850 has a maximum power draw of 98W. Seeing as power consumption was one of the 2900 cards’ main problems, this is a damn good thing.

Secondly, if the dies are smaller, then you can get much more of them on a wafer, which means greater yields (ATI promises wide availability from the launch date of 15 November) and lower costs. The latter is key here, as the Radeon HD 3850 that we tested is scheduled to cost under $200 US, making it a replacement for the lamentable Radeon HD 2600-series cards and therefore a rival to the GeForce 8600-series, as opposed to the new GeForce 8800 GT.

Sapphire has already announced that its own version of the 256MB card we tested will cost just £110 inc VAT, which makes it an absolute bargain. Why? Because it has very similar specs to the Radeon HD 2900 cards, as opposed to being the usual crippled mid-range GPU. Of course, it’s worth bearing in mind that 256MB GeForce 8800 GTs will be available soon, and they may well out-perform the 3850 at their estimated price of £123.30, but we’ve yet to test one of these in the labs.

Anyway, back to the 3850, the chip has 320 stream processors, 16 texture units and 16 ROPs, with the core clocked at 669MHz, and the GDDR3 memory clocked at 829MHz (1.669GHz effective). The only downside, as far as we can see, is that the cards only come with 256MB of RAM as standard, and only have a 256-bit memory bus. However, this should only become a problem at very-high resolutions (above 1,680 x 1,050), at which a mid-range card shouldn’t be expected to play games anyway.

Radeon HD 3850 architecture Global Illumination in DirectX 10.1

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