PhysX on graphics card

[kalniel]

Just read this snippet at anandtech.com regarding the new GTX 280/260 cards.

Originally Posted by dailytech

The GTX series is NVIDIA's first attempt at incorporating the PhysX stream engine into the D10U shader engine. The press decks currently do not shed a lot of information on this support, and the company will likely not elaborate on this before the June 18 launch date.

I'd not heard this anywhere else, but could explain what looks like an enormous chip size.

Think it'll work?

[aidanjt]

It'll easily work if they implement the sub-system in the drivers correctly.

[dangel]

I think i'd rather one of my cpu cores did the work and the gpu got one with what it's best at

[aidanjt]

Realtime physics processing is pretty intense floating point work, not very well suited to general processing architectures like x86 & x86_64, GPGPUs on the other hand, are very well suited to this type of work. Probably the best bet is to get a cheap lowish end GPU to do physics, and a beefier card for the graphics work. With this kind of subsystem in place, physics nerds in the games developer offices are going to be drooling.

[moogle]

Originally Posted by dangel

I think i'd rather one of my cpu cores did the work and the gpu got one with what it's best at

I'd like that too, but the GPU can do more than the CPU can't it? (Processing-wise)
It'd be good if in SLI the rest of the 2nd card handling the Physics and still doing what it does in SLI would make it less of a waste (ie less then 2x the performance)

[p5-]

Does anyone know what the ATI equivalent Physx processing will be in their HD48x0 series?

[kalniel]

Originally Posted by p5-

Does anyone know what the ATI equivalent Physx processing will be in their HD48x0 series?

It'll be a little tag that says 'Nvidia didn't license the technology to us so we can't put it on our hardware, try the CPU* next time'

*CPU is doubly good because our chums at Intel have the /other/ physics license too.

[moogle]

Originally Posted by p5-

Does anyone know what the ATI equivalent Physx processing will be in their HD48x0 series?

none afaik.

[dangel]

Originally Posted by moogle

I'd like that too, but the GPU can do more than the CPU can't it? (Processing-wise)

The problem I have with the whole thing is that you don't *need* insane amounts of physics processing power for most games - and if if you did you'll still need a heck of a lot of graphics power to render it all. And so that leads me to think for the relatively simple physics of yer average 2008 game you might as well use a CPU core (or two) as they're hardly oversubscribed on a quad core system.

So what of the future? Will graphics cards be so powerful as to be able to spare some processing units for physics as well (or will they continue to be loaded with more and more eye candy keeping them as busy as they are now)? And what of the CPU - if it has 8 or 16 cores why not use them for physics?

I've never been convinced by the SLI arguement for graphics and i'm even less so for physics - I don't want to buy a second card for it (nor do I want to keep the power hungry monster I have now when I upgrade) as was the case for most when looked at phsyx cards. Yes nVidia will make it more popular but we'll still see games needing a fallback mode for ATI (or other) owners or people with just one card (who'd prefer higher fps). It'll take someone like MS to make it mainstream really - by tying it up in directx or similar. Then the choice of hardware to do the job will be up to us, not one manu.

[moogle]

they may be simple physics for stuff like explosions and bouncing objects etc. but what about deformations and other complex effects. If 1 cpu core could do that I'd be happy with that and not buy a physx card or an extra physics gpu.

[this_is_gav]

How reputable this is, or even whether it's a hardware based thing or just a driver emulation trick of some description, I've no idea, but:

TG Daily Exclusive – We previously published several details about AMD’s next-generation graphics card lineup and as we get closer to the launch we are getting more details about the launch date, feature set and prices. The good news: The new boards will come with “physics processing capability” and prices that will start below $200 for a 512 MB board. The bad news: The 4800 series will launch after Nvidia’s GT200.

Source: TG Daily

[shaithis]

Useless until graphics cards are so powerful that they max all your cpu cores, while having time to twiddle their thumbs.

Most people have between 1 and 3 cores idling while gaming whilst their gfx card is going flat-out. Use the CPU cores for crying out loud, I've been saying it since the first physics card was announced!!

I am guessing that games such as Crysis, Bioshock and Lost Planet etc are already doing some physics on the extra cores.......just need more developers to follow suit and then maybe we can dispense of these "it sounded a good idea at the time" solutions.

[kalniel]

If Intel open up the Havok stuff to AMD then I'm sure we'll get decent CPU physics, possibly through some nice SSEs or similar. I agree, while well suited for the job, I want my GPU to be fully used doing something else for the most part.

[DanceswithUnix]

But all Nvidia chipset motherboards will be coming with integrated graphics capability from now on, so hopefully in future they can use those streams for physics and let the plug in graphics card do just graphics and the CPU cores do networking & AI.

Would "physics on the motherboard GPU" sway your mobo purchasing choice?

[aidanjt]

Originally Posted by dangel

The problem I have with the whole thing is that you don't *need* insane amounts of physics processing power for most games - and if if you did you'll still need a heck of a lot of graphics power to render it all. And so that leads me to think for the relatively simple physics of yer average 2008 game you might as well use a CPU core (or two) as they're hardly oversubscribed on a quad core system.

Sorry, I just plain can't disagree with that more. The calculations that figure out how to perform accurate raytracing, collision detection, tesiliation, and shadow texturing is all physics, so to are the fluid dynamics that makes water appear more realistic. Complex physics is an intrinsic part of 3D gaming, always has been, and it will only evolve even more in the coming years.

You think physics is a new fad in gaming, it really isn't, it's always been there, lurking behind the scenes, now it's just jumping out and yelling 'rowr' because of the more obvious gravitational and 'bounce' effects in modern games. GPUs can handle it, it's the proper place for it, there's no need for a PPU co-processor (as we saw with ageia, that was a flop), or waste CPU cycles that could be better spent on things like AI and complex audio algorithms.

[shaithis]

Originally Posted by aidanjt

GPUs can handle it, it's the proper place for it, there's no need for a PPU co-processor (as we saw with ageia, that was a flop), or waste CPU cycles that could be better spent on things like AI and complex audio algorithms.

Then why is my CPU at 30%ish while gaming, overclocking my CPU further has no effect on framerate but pushing my gfx card further shows immediate benefits?