The first demonstration showcased the lighting capabilities of ATI's future card. Like the GeForce, ATI's product supports eight hardware lights, but in a more efficient manner. Using the Glaze 3 utility, ATI demonstrated that under a full load of eight hardware lights, performance was reduced by 45%, while on "other" T&L engines performance would drop by approximately 60%. Made possible by optimized circuitry, ATI has gone to great lengths to ensure that their T&L pipeline will always stay busy (pointing out that one of the worst performance hits occurs when an engine is waiting for data due to an poorly optimized pipeline).
We tried to get information about the board layout, but since it wasn't a production product we weren't allowed specifics. In the short time we looked at the card, we did manage to copy down the data silk-screened on the surface of the RAM and found that ATI was using 6ns DDR Hyundai memory (more than likely 32MB).
At over 60fps in Quake III at 1024x768, we are looking at close to 90fps for the shipping product (if the 2/3 performance estimate proves accurate). With this kind of performance on a single chip solution, we hope with fingers crossed for a dual-chip SKU sporting massive amounts of memory bandwidth providing for the rich quality features ATI has incorporated into the Pixel Tapestry.
Claiming their next-gen product will be competitive, it will be interesting to see if ATI will be able to leapfrog NVIDIA's dependable six month product cycle and top-notch performance and 3dfx's anticipated T-buffer. Only time will tell, but you can be sure that we will have the skinny in the very near future.
One of the most interesting things we saw at the show was GigaPixel showing off an actual working board, their GP-1. Vaporware it is not.
Founded in August of 1997, GigaPixel offers IP (intellectual property) cores for the products of others. That means they don't plan on selling any boards of their own, rather, they plan on selling their design to others.
Highlights of their GP-1 design include: 4x, jittered, multi-sample anti-aliasing at full speed, visibility culling, and improved memory bandwidth handling.
Visibility culling is achieved through a system somewhat like VideoLogic's PowerVR series. The GP-1 takes 32x32 pixel tiles, determines what polygons are visible, and ignores the unseen polygons. This allows the GP-1 to render far fewer textures than traditional cards, which render every polygon. This technique saves heavily on memory bandwidth, especially in newer games with more complex scenes. GigaPixel claims around a 10X cut in memory usage.