Overclocking Extravaganza: Radeon HD 4890 To The Max

Final Words

All but two.

That's how many benchmarks in which our 1GHz/1.2GHz (core/mem) Radeon HD 4890 lead the stock NVIDIA GeForce GTX 285. That's nothing to sneeze at. Certainly it doesn't mean that the 4890 is faster or better than the GTX 285, especially because the GTX 285 can be overclocked as well to improve performance. What this does mean is that for about $100 less we have the potential to achieve the stock performance of NVIDIA's flagship single GPU part with a highly overclocked AMD GPU. From an end user value perspective, that extra $100 is there to ensure you get at least the performance of the GTX 285 along with any potential overclocking benefits you might have from the higher end part. There is still reason to buy the GTX 285 if you need even more power. But this is quite intriguing from an architectural perspective.

These tests show that there is the potential for a 959 Million transistor AMD GPU to consistently outperform a 1.4 Billion transistor NVIDIA GPU in the same power envelope at 55nm with similar memory bandwidth.

Yields and business being what they are, it doesn't make sense for AMD to push out a part at the extreme clock speeds we tested. But from an engineering standpoint, even with the smaller die, less is more, multiGPU at the top end strategy, AMD has built a part that can (when overclocked) best the stock performance of top of the line NVIDIA hardware designed to pack as much power into a single GPU as possible.

And that seems pretty significant.

At the same time, while we don't have any solid standardized OpenCL tests to run as of yet, it appears from some limited applications like folding@home and others that NVIDIA's approach may be better suited to GPU computing or more general purpose or flexible applications beyond gaming. We can't really confirm this theory yet, as there isn't a wide enough range of GPU computing applications, but it might not be that NVIDIA has been pushing CUDA so hard because they know it to be an advantage, not just in terms of software support and a feature check box, but in terms of a fundamental performance or architectural edge for these algorithms. The architectural path NVIDIA has chosen may well prove useful when DX11 hits and we see a further push away from DX9 towards really deep programmability and flexibility. Only time will tell on that front, though.

In the meantime, NVIDIA's margins are much tighter on their larger GPUs and now their single GPU performance advantage has started to erode. It seems the wonders of the RV7xx series have yet to exhaust themselves. Competition is indeed a wonderful thing, and we can't wait to see what comes out of the upcoming DX11 hardware battle.

For now, at resolutions below 2560x1600, the Radeon HD 4890 has the advantage. At 2560x1600, the lines become a little more blurry. For stock hardware the GTX 285 is still the fastest thing around in most cases. But if you want to take your chances with overclocking, 30" gaming on a single AMD GPU just got a lot more potentially attractive.