After a recent discussion with Agent, I thought it' d be a good time to talk about upcoming graphics cards from ATI/nVidia (R7xx/GT200). Both are due out within the next month or so. All is still speculation.
It' s actually quite unusual to have so little information about the cards when they' re both so close to release, but there are tidbits of information around that should give us a general idea of what they' re made of. I mainly refer to the high end parts in this post.
ATI RV770 (4000 series) 
The R600 series from ATI was a flop. It was fundamentally crippled in a number of ways. R700 is an extension of R600 but looks to solve a couple of grievous problems such as doubling the amount of TMU' s that R600 had, one of the reasons it performed so poorly. You may look at those specs and think RV770 is bandwidth starved, with only a 256 bit interface, but this will be countered by GDDR5 RAM which runs at very high frequencies. Another rumor is that their X2 cards have a unified memory approach, allowing both GPU' s to access any amount of the 1GB of memory. Not only does this save manufacturing costs, it also allows for some performance gains if implemented correctly. Also a new is the asynchronous shader/core speeds that it has. Much like what nVidia did with the G80, the RV770 will run its shaders at a speed faster than the core.
An interesting thing is that ATI looks to be going for a power saving approach. I am grateful for this as graphics cards are fast becoming bloated power hogs. It' s about time they took a page from the CPU world and adopted some efficiency. Only consuming 10W of power at idle is impressive. 25W for dual.
Another interesting tidbit is the possibility that in reality, RV770 has 800 SP' s, but 320 of those are devoted to physics computation (hence leaving 480 real shaders). This story surfaced only recently and may be bogus. But it does make sense considering Intel has Havok, and nVidia has PhysX. ATI probably does not want to get left out.
Finally, the most attractive thing about RV770 is the price, most recent rumours suggesting their high end single chip solution going for just over $200 US at launch and probably dropping below that soon after. So as far as bang for buck, RV770 looks to be impressive.
nVidia GTX 200 
Even less is known about the GTX 200 but this list that surfaced recently looks realistic enough. Again, the GTX 200 is an extension of the G80 architecture. First off, we can see nVidia is sticking with GDDR3 memory, but countering bandwidth problems by having a 512 bit interface. This is pretty much the exact opposite of what ATI is doing and should end up with comparable results. It also has PhysX support, undoubtedly from their acquisition of Ageia. CUDA support is also there.
nVidia has in all likelihood gone with a big monolithic design for their high end stuff, rather than look at multiple chips like AMD. This is probably the last time that they' ll be able to do this, as graphics cards these days consume too much power. Much like the Pentium 4, you can only go so far on raw clockspeed and brute force.
Another interesting thing is that the GTX 200 doesn' t seem to support DX 10.1. Now this isn' t a huge issue but it suggests a limitation with the overall architecture with regards to implementing it. It remains to be seen whether DX 10.1 holds any real merit.
Other than that, not much else. All of this is still speculation and could change. I think it' ll be pretty close to what' s here. nVidia will probably have the performance lead but it will come at a cost. ATI will be better at multiple GPU' s. Overall, I' m kind of leaning toward getting an ATI card this next time round. Being incredibly cheap even for their high end parts and the energy saving features really make it stand out more. If I can get a couple of 4870' s cards for a similar price as a single GTX 280, then I' ll definitely consider taking the plunge into Crossfire.
< Message edited by UnluckyOne -- 19 May 08 7:23:46 >