Conclusions
We’ve seen some very interesting results from the ASUS PhysX P1. Well, not so much the ASUS PhysX P1 as the AGEIA PhysX PPU. What we can say about the ASUS PhysX P1 is that it is a very nice card, has a more than adequate cooler that is also relatively quiet, and does not consume much extra power at all. We also liked the AGEIA by PhysX logo they slapped onto the front of the faceplate; it adds a very nice touch to the rear of the computer. We don’t have anything to compare it to, so we can’t really say if it is better or worse than the competition. But it does have high quality capacitors which is something we like!


AGEIA’s PhysX PPU is a singular product that we feel is still very much in its infancy. What we have seen from our GRAW tests is that the technology, while promising, is not implemented in mainstream games to the extent it could be. In our custom explosion test it was readily evident that the visual splendor of the scene increased somewhat dramatically, but it came at the expense of frame rates. This is due undoubtedly to the video card having to foot the extra rendering load created by all of the additional particles. There was also the confusing result of the insignificant difference in CPU load from running our test with and without the PhysX PPU installed, an anomaly we still don’t have an answer for.

It is unfortunate really, that the PhysX PPU has such mediocre software support at this stage. The technology in the card, in our opinion, is clearly powerful and has a tremendous amount of potential. However, there are no games, at least no games that anybody is really going to want to play, that support the PhysX technology. The games are coming though, they are definitely coming. Games like “Joint Task Force” look like they will be able to make use of the PhysX technology on a grand scale, as do games like Unreal Tournament 2007. The upcoming PhysX patch for Rise of Nations: Rise of Legends also promises to bring another level of realism with the increased detail that the PhysX PPU will afford. There is no doubt in our mind that hardware accelerated physics is going to absolutely take off over the next two years, but at this point, everything just seems... not ready.

Right now, it seems that the only real competition for AGEIA is time. The time it takes for these killer applications to come out that will make the PhysX card worth its weight and some. We see this problem as two-fold. On one hand, if these games take too long to come out, the general consumer base that AGEIA is targeting might lose interest in the product, and the PhysX PPU might slip from the limelight and end up going the way of a certain product from a company that starts with an “R” and rhymes with “Wrambus.” We would hate to see this happen, as we have already stated we think that the PhysX PPU, the ASUS PhysX P1 in particular, is a great product with tons of potential. However, it is a possibility. On the other hand, there are two quite viable alternatives to the PhysX PPU in terms of hardware acceleration solutions currently in the works. One of these alternatives is, or at least appears to be, a far more viable option than the other. The first, and what we consider a far less-likely option, is that the advent and implementation of multi-core CPUs, not just the quad core behemoths that will be upon us shortly, but processors like the Cell that will use around nine different, specialized cores to complete different tasks, will handle the physics calculations. We see a couple of problems with this. The first problem is that modern CPUs, while absolutely incredible at general computing tasks, are less than spectacular at specialized calculations like video rendering and physics (hence the implementation of dedicated GPUs some 15-ish years ago). A processor that is specialized to the extent of a PPU will always be superior at performing the linear algebraic functions necessary to do physics calculations. The second potential problem with this solution is that while hardware grows, software grows alongside. Applications and even operating systems in the future will be largely multi-threaded. Taking away from the CPU time of these applications could have adverse affects on the performance of your computer beyond what we have seen today.

The second, more viable solution, is the use of a technology called Havok FX. Havok, the undisputed heavyweight champion of software physics for many years now, announced back in November of 2005 that they would actively be developing a technology to compete with AGEIA’s recently announced PhysX PPU. Game developers, and indeed gamers, are quite familiar with Havok physics engines. It is, after all, a modified Havok 2 engine that makes up the lion’s share of a game engine we have come to know as “Source” (Half-Life 2). Havok FX technology is rumored to offload physics calculations from the CPU and make use of the idle time experienced by modern GPUs. While most modern GPUs are actually pushed to their limits by current games, there are features on almost all graphics cards that are largely unused. While the specifics of how Havok plans to balance the physics load with the graphics load are not yet known, it is clear that a multiple-GPU solution would be far more suited for such a task than a single video card. In fact, ideas have been flying around in the minds of NVIDIA and ATI that involve crazy things like 3 dedicated graphics cards (one being for physics) and multi-card, multi-GPU setups. While it would seem that a specialized physics processor would be superior to a GPU in terms of efficiency, there is no way of verifying this assumption. If a multi-GPU solution does indeed turn out to be a viable alternative AGEIA’s PhysX PPU, we will have a hard time advising people to disregard the obvious flexibility advantages that such a solution would have over the PhysX.

It is because of all the reasons stated above that we simply cannot recommend AGEIA’s PhysX PPU to the mainstream gaming audience. For the ultra-enthusiasts that seem to have bag fulls of loot hidden under their beds, go for it. The enhanced visual affects afforded by the PhysX PPU will not be matched for at least another few months, and by that time you should see a considerably larger amount of hardware support for the card. But as it stands, the average consumer and even most enthusiasts stand to gain very little from the AGEIA PhysX PPU. About four months from now it could and most likely will be a completely different story, as games will have come out that benefit insanely from a dedicated physics processor. AGEIA’s PhysX PPU is a product that just seems to have been launched before its time, the rest of the world just needs to catch up.

Read the addendum to this article, which includes performance numbers from CellFactor, here.