It's both the most advanced and most graphically demanding PC game yet. Our first performance test is the 3D technofest that is Crytek's Crysis. You'll do well to get any change out of £400 for a GTX. And remember, prices for the 4870 kick off at just under £200. What you really need to know is just how close the 4870 gets to NVIDIA's finest. The 4870 is a dual-slot board that requires two six-pin power cables where the 4850 is a single slotter that can survive with a single power cable.Īnywho, you can read all about the GTX 280's architectural nitty gritty in our review. The only other significant difference is a change in form factor and power consumption. But it's nothing like as big as it would have been had ATI stuck with GDDR3 for the 4870.

Factor in the GTX's 2.2GHz GDDR3 frequency and it retains a raw bandwidth advantage. That's an extremely important upgrade because NVIDIA's beastly GeForce GTX 280 has the advantage of a much wider 512-bit memory bus. But ATI has bolted the very latest 3.6GHz GDDR5 chips to the 4870. The 4850's GDDR3 memory trundles along at a relatively pedestrian 2GHz. In terms of core frequencies, it ups the ante by 125MHz to 750MHz. The 4870, therefore, is all about clockspeeds. After all, both are based on the RV770 GPU. Likewise, it sports an identical DirectX 10.1 feature set (something NVIDIA cannot yet match, for better or worse) and the same 256-bit memory bus and 512MB frame buffer. It has the same 800 shaders, 40 texture samplers and 16 render output units.

In many respects, the 4870 is no different from the cheaper 4850. But to recap briefly, the really clever bit is how ATI has managed to up the shader and texture count by 150 per cent courtesy of a boost in transistors of just 40 per cent. You can find full technical details of the silicon gubbins that lie at the heart of the 4870 in our original Radeon HD 4800 series review.

Ati radeon hd 4870 1gb