ATI Radeon HD 4870 in Graphics cards

With 800 stream processors and up to 1GB of GDDR5 memory, it's clear that ATI's Radeon HD 4870 means business. It's the flagship of the 4000-range - before the dual-GPU X2 products are accounted for - and, as such, delivers a set of blistering benchmark results and specifications that impress.

As well as the new GDDR5 memory, which is an innovation that no Nvidia card can boast, the 750MHz clock speed is 125MHz higher than the HD 4850. But the HD 4870 does share several characteristics with that product: both cards contain 956 million transistors, a 256-bit memory bus width, and support both Shader Model 4.1 and DirectX 10.1. Like all current ATI cards, it's manufactured on a 55nm die.

The increased clock speed and GDDR5 memory contribute to impressive benchmark results. The HD 4870 ran at 42fps in our 1,680 x 1,050, high Crysis test, and struggled only when we ran the same benchmark at 1,920 x 1,200 with quality settings at very high. Call of Duty 4 and Far Cry 2 were playable, with the HD 4870 untroubled even at the highest resolutions and quality settings.

The HD 4870 stacks up well against opposition from Nvidia too. While no cards offer a direct parallel, at least in terms of price - the 9800 GTX can be had for around £134, with the GTX 260 costing £179 - the HD 4870 provides healthy competition for both, even though the GTX 260 is almost £20 dearer.

It was faster than the 9800 GTX in every game we tested, with 81fps compared with 64fps from the Nvidia card an especially telling victory in our highest Far Cry 2 benchmark. It's even quicker than the GTX 260 in most of our benchmarks, with only Call of Duty 4 seeing the Nvidia card pull ahead - and even then it's only by 6fps, scoring 78fps compared to 72fps from the HD 4870.

It's another triumph for ATI, then - a fitting end to a year where the company has successfully reversed the ailing fortunes of its desktop GPUs and turned the screw on Nvidia. For those gamers who simply can't afford an HD 4870 X2, the HD 4870 is a fantastic combination of price and performance - and a worthy Labs Winner.

Author: Mike Jennings