The PhysX Card
Thursday, March 23, 2006 2:41:56 AM
Come back to the present. Today, for the first time, a hardware board with a new type of processor (called a PPU or physics processing unit) that does hardware physics processing is available (not for retail yet but if you buy a specific Dell, Alienware or Falcon Northwest PC then you can get it put in).
Seen as the next major revolution in gaming, this board does exactly what it was meant to do: take the burden of physics processing off the CPU and up the detail a hundred times or so. Supposedly, these cards can calculate and keep track of somewhere in the vicinity of 30,000 individual particles onscreen at once. The CPU can barely do a fraction of that. So, it makes sense to have such a thing in, right? It does to me anyways.
Now, there are some that'll say that these new physics cards are unnecessary because there are other places to put physics processing. Some mention the new dual-core CPUs; others mention the video card or more recently, the second video card in an SLI/Crossfire setup. nVidia recently made an announcement to this effect.
I'm not going to pass myself off as an expert on such things but it's my gut feeling that a dedicated physics card is the best solution. If use put the physics processing on the second core of a CPU, you still probably won't be able to have the same number of particles onscreen at the same time as you would with a dedicated card. Additionally, when games start to take more advantage of dual-core processors, you'd most likely be right back where you started. If you were to put the graphics on the video card, you'd end up with one of two scenarios:
1) You'd dedicate a certain amount of video card processing power to the physics calculations which instead could've gone to video processing which could've made for higher quality graphics settings in applications (same could be applied with SLI/Crossfire when games start using the second video card more as well) or
2) You end up with, design-wise, a more complex (and perhaps bigger ) video card and with the way things have been going in the past few years and with jesting not too long ago of dual-core GPUs, I don't believe that will be perceived as worthwhile (at least to me). Plus, if this way happens, the video card might even be more expensive and have you checked the prices of high-end video cards recently? They're upwards of $500 in some cases!
Now, that's not to say that I'm against physics processing on video cards. I know a lot of people are budget-minded and wouldn't drop $250-$300 (the supposed retail price on the PhysX cards) on another piece of hardware. For those people, I think having video cards doing physics processing in the style of #1 wouldn't be too bad, assuming you can disable the physics processing if you so desire.
There are additional potential applications for such cards. Anyone running Folding@Home or another such distributed computing client could potentially benefit from using these cards solely for their efficiency. I can also imagine CGI and other scientific and modeling applications getting an advantage from these cards.
There are downsides currently. The potential scientific and modeling markets aren't even being targeted yet; gaming is, so far, the sole purpose of hardware physics. Secondly, there isn't a standard library/API like OpenGL or Direct3D and there would need to be in the future if these things really take off. OpenPL anyone? But frankly, the biggest obstacle the PhysX cards have to overcome in the short run are is a lack of software that can take advantage of such technology. BFG, so far the only announced retailer of the PhysX cards, is holding off selling the cards until May when there are games out that would take advantage of them. Though there are games that will eventually take advantage of the hardware.
So what does all this mean? I don't know exactly and really, no one does. Will these PhysX cards take off or will they go the way of the dinosaurs? Personally, I'm optimistic and believe that these physics cards are the first in a new generation of hardware. Perhaps in 5 years of so, we can look back and remember a time when we bought our first physics cards.
Additional links and general reading:
http://www.pcper.com/article.php?aid=225 -- technology preview
OK, I'll get back to studying now.
I found an image that Ageia has been using to better illustrate the PPU's place in computing. Here it is: