We downloaded the new version of the demo that was released on 13th of June to see if there was in fact a major improvement from release 35 with the collisions of rigid bodies. We also wanted to see what the impact of added fluid and cloth simulations was, both with and without the card. Below is a snippet from the notes for Cell Factor release 36.
We started testing the graphics cards in the order of most powerful to the least. We generated figures in release 36 with the GeForce 7950GX2 while the PhysX card was enabled and the demo was run with PhysX on. However, when we switched off the PPU and ran the demo in software mode, we could not get near any of the simulated cloth. The second we turned the camera in the direction of the cloth and moved physically close to the hanging cloth strips near the tunnel entrances or the flag hanging on the upper deck, the frame rate would plummet and the game would slow to a crawl. We continued testing with all of the cards down the line and we encountered the same situation.
This is what the hanging flag will do with the PhysX card enabled. Notice how the cloth sways in the breeze and when shot, it tears into shreds.
When PhysX is disabled and the demo is run in software mode, we can move the camera freely until the camera comes close to looking at the flag. Then we instantly drop to one frame per second.
Below is an image showing the dual cores of the AMD Athlon 64 FX-60 instantly being given large amounts of work to do. The frame rates suffer from a smooth data flow from the CPU. Based on what we have seen, the cloth simulation inside Cell Factor is brutal and will need hardware acceleration.