Ever since Intel released the Core Microarchitecture in the middle of 2006, the processor business has been a bit like watching Mike Tyson go a few rounds with Rick Moranis – amusing, but rather a foregone conclusion.

At least the never-ending slugfest between ATI and Nvidia has been showing some signs of life. In June, however, it will be shaping up to be a prize fight of heavyweight proportions.

Over the last few months, more and more conclusive details have been trickling out about what ATI and Nvidia actually have planned and when.

It’s looking like ATI’s RV770 will arrive on June 16, with Nvidia’s reposte officially launched just a couple of days later. We’re back to the synchronised releases of old, and there's the potential for a real grudge match ahead in the second half of 2008.

Enter the ATI RV770

Back in February, NordicHardware leaked fairly comprehensive information about ATI’s RV700 series cards. According to the Scandinavian rumour-mongers, the flagship Radeon HD 4870 will have 480 stream processing units (SPUs), which is 50 per cent more than the current Radeon HD 3870’s 320 SPUs. So the new card could be at least 50 per cent faster than the old one.

This was little more than gossip a few months ago, but it has recently been corroborated by another leaked posting from a Folding@Home forum.

For those who aren’t familiar with this distributed computing initiative, developed by Stanford University, Folding@Home runs as a screensaver, processing biochemistry algorithms with spare clock cycles.

ATI has been working closely with Stanford University on a GPU-powered client, which was released in late 2006. So the Folding@Home team is likely to have similar inside information to other software development partners.

Engineering samples of RV770 PRO have been spotted in the wild running at 625MHz. But the 4870 could have a clock frequency of over 1GHz, a bit more than the Radeon HD 3870’s reference speed of 775MHz. ATI also looks likely to keep up the trend of memory early adoption, with GDDR5 on the cards for some versions of RV770.

The Nvidia GT200 strikes back

Nvidia has traditionally been better at keeping its GPU plans secret. For the last few months, the new GT200 looked set to be launched on June 18 as the GeForce 9900 series. This would have been another example of Nvidia's recently rather confusing naming strategy.

Fortunately, it now appears that Nvidia has realised the absurdity in having two cards called 8800 GTS with considerably different GPUs inside, whilst the 9800 was launched with a faster version of one of them. The current word on the street is that GT200 will be launched as the GTX 280 and GTX 260.

The actual specification of Nvidia's GT200 is a bit more mysterious than ATI’s RV770. But recent guesses have given it 240 SPUs, 32 raster units, 1GB of GDDR3 and a 512-bit memory controller. That’s nearly twice as many SPUs as the GeForce 9800 GTX.

Nvidia’s SPUs aren’t quite the same as ATI’s, and the fact that the GT200 may only have half as many as RV770 is no indication of relative performance.

Since G80, NVIDIA’s GPUs have run different parts of their core at different speeds, with the SPUs operating at 2.5 times the rest of the GPU. With the current 9800 GTX, the core is clocked at 675MHz but the shaders at 1688MHz. We haven’t seen any indication of GT200 GPU and memory speeds, though.

Let battle commence

ATI is also continuing with the dual-GPU strategy of its 3870 X2, although this is not quite what was rumoured for R700 last year, which had as many as eight GPUs on one card.

So in the red corner we have the ATI Radeon HD 4870 X2, with two 480 SPU-equipped GPUs running at over 1GHz each. In the green corner will be the Nvidia GeForce GTX 280, with 240 SPUs. Place your bets now. This battle is going to be a humdinger.

GeForce9900.png – The rumours are flying in the run-up to the two biggest graphics card launches of 2008