The FPS issue

Havok: From our inspection, differential effects in the GRAW PC game when using the PPU are not significantly obvious – but where they can be observed, additional particles do not appear in volumes greater than 100’s of particles (a range that is typically easily in the domain of the CPU/GPU for particles). These observed particle effects are also only particles and not apparently persistent rigid bodies. They pass through the environment after a short time (seconds) at most. User comments back this up:
“…to be honest it looks exactly same with the PPU as it does without it, the only difference is you get the extra blocks/debris, the strange thing is these extra blocks/debris seem to appear unrealistically out of no where when you shot things like the wall, floor etc, it really is like they've just been tacked on just to say *this game supports PhysX*.”

Consumer reports from users who already have purchased the PPU and GRAW indicate that the PPU “actually slows down the game” in moments when effects are generated that are unique to the PPU. The effects described above appear to be the cause of the slow down – our observations here using a DELL/PPU confirm this. Also see http://forums.overclockers.co.uk/showthread.php?t=17568825.
One user comments states:

“10-16 FPS slower with hardware PPU, I guess I need another GPU (SLI) to help render the added debris and effects I get from using the PPU, the price of PC gaming just went up again :-(, I can't believe that I have to disable the hardware PhysX card I just paid 200 quid for so that I can play GRAW at an acceptable FPS, to be honest I just feel like giving up on PC gaming these days. “


AGEIA: Consider first that PhysX is focused on enabling an entirely new experience in gaming in which literally 1,000s of objects of differenct types can move, collide and interact. Up to now, this has not been possible. The goal of PhysX is to enable this new class of complex physics algorithms to be processed within a more than acceptable frame rate. Of course, depending on the game and the PhysX implementation and the rendering capabilities of the system, there may be occasional momentary frame rate impact, but on average, we don’t expect this to be significant.

It’s unclear how this individual measured frame rate impact, however we aren’t keeping our heads in the sand. We appreciate feedback from the gamer community and based partly on comments like the one above, we have identified an area in our driver where fine tuning positively impacts frame rate. We made an adjustment quickly and delivered it in a new driver (2.4.3) which is available for download at ageia.com today. That’s the beauty of the PhysX solution. A powerful processor is in place now and a flexible software solution is there to continue improving the PhysX experience for our customers. Buy a PhysX accelerator today and it keeps getting better.


Havok: AGEIA appears to imply and consumers conjecture that the PPU is generating so many objects that the GPU cannot handle the load. Multiple direct tests on the game by using NVIDIA’s and ATI GPUs indicate the GPU has room to spare and in fact, if the PPU is factored out of the game, that the particle content generated by the PPU can easily be drawn at full game speeds by the GPU. So the introduction of the PPU most certainly appears to be the cause of the slow down in this case. NVIDIA specifically can technically verify that the GPU is not the cause of the slowdown.

AGEIA: While we believe that a high-end system configuration of leading edge CPUs and GPUs is always a good thing, PhysX does not require it. Today’s powerful CPUs are quite capable of excellent game AI and logic and the newest GPUs are well positioned for rendering and displaying images.

Users can make up their mind on their own about the best solution for physics. You can already see responses to the above notion on other gaming forums. GRAW and other titles today are good, but they are only the beginning....

http://www.hardforum.com/showthread.php?t=1051457

“Funny, since the "physics" in GRAW seems to be the same kind of effect physics that HavokFX is all about... I wonder why they didn't comment on CellFactor ..or do I?”

USER RESPONSE TO ABOVE

“I think that's pretty much what you can expect to see in the near future... Developers are unlikely to make gameplay dependent on the presence of a PPU until it's widely adopted. Until then it'll probably be limited to effects (and taking the gameplay physics load off the CPU).

So what do you believe? The truth is that support for the AGEIA physics chip is still very early with only two games out there – City of Villains and Ghost Recon: Advanced Warfighter (another game, the RTS title Rise of Nations: Rise of Legends, is due out next week). As such, game developers may simply have not had the chance to fully exploit the uses for the physics chip, much like how the first games that use graphic engines like Epic's Unreal or id's Quake didn't look as impressive as later games that use the same graphics engine. In the months to come a more complete picture of CPU-GPU vs. PPU game physics support will emerge as more games come out, and more developers have a chance to use the features from both Havok and AGEIA. Much like the battle between VHS vs Betamax and the current HD-DVD vs Blu-Ray, the final victor in the game physics wars will depend on consumer support.