PPU-Physics Processing Unit

Ace Pace · Post by **Ace Pace** » 2005-03-08 02:00pm

As per the Inq and GS(courtesy of an interview with Epic)

Is this neccesary at all?

I can see this being a nice addon chip, but I don't think enough people would buy this and make this actully used beyond a couple of niche games.

SPOOFE · Post by **SPOOFE** » 2005-03-08 03:23pm

Is this neccesary at all?

Yup. The maths required to do the physics calculations in games such as Half-Life and Far Cry etc. etc. take a shitload of system resources, especially compared to other non-graphical utilities. Original 3D add-in cards were originally designed to take a lot of tasks off the shoulders of the CPU... this is a logical next step.

Vendetta · Post by **Vendetta** » 2005-03-08 03:39pm

3D graphics cards were able to take off a lot quicker though because they have a visible effect for the amount of money spent.

Physics processors for games would have a much more subtle effect, so they'd need to be a lot cheaper to take off in nearly the same way. They won't become indispensible in the way VGA cards to gamers for some time unless developers force the issue (and they won't, because only the top few are compentent enough to work with middleware physics properly and only a small fraction of games can use real physics.)

Hamel · Post by **Hamel** » 2005-03-08 03:39pm

Havok goes to town on my cpu when lots of stuff is going on. Launching an smg grenade into a pile of crap will cause the game to actually halt for 1/8 of a second. Having dedicated hardware to take care of the problem would be great, but there's always expense to worry about

Pu-239 · Post by **Pu-239** » 2005-03-08 04:27pm

Couldn't a GPU be used to do some physics calculations (among other things)? And if not, what about including a PPU on high end graphics boards in order to gain adoption?

Dahak · Post by **Dahak** » 2005-03-08 05:29pm

Pu-239 wrote:Couldn't a GPU be used to do some physics calculations (among other things)? And if not, what about including a PPU on high end graphics boards in order to gain adoption?

GPUs, at least the "gaming" variety, are highly specialised for graphic calculation, and are also a bit lacking in mathematical accuracy needed for this kind of calculations. They are no general purpose processors.

Alan Bolte · Post by **Alan Bolte** » 2005-03-08 05:44pm

Pu-239 wrote:what about including a PPU on high end graphics boards in order to gain adoption?

Bandwidth cost, power consumption, space on the card, am I missing anything? On the other hand, if standalone cards don't take off, then selling a line of 'gaming' cards with both a GPU and PPU along with the less-expensive line of graphics cards might. But I think AGEIA has the right idea in trying to sell stand-alone cards first. Especially considering that major game developers are quickly getting on board.

Now, as to "is this necessary?", well, I'm not entirely sure it falls under 'necessary,' but it would certainly be useful, and if this can be made popular, then it wouldn't be a bad thing. The thing of it is, it will have a visible effect. If it was just effecting minor improvements, I'd be extremely skeptical, but a thousand-fold increase? Like the articles say, that brings things like much more believable fluids and destruction of objects, which are just as visible as purely graphical improvements.

Praxis · Post by **Praxis** » 2005-03-08 06:27pm

Forget the Cell, this would be sweet in a next generation console

Executor32 · Post by **Executor32** » 2005-03-08 07:00pm

I'd buy that for a dollar!

MKSheppard · Post by **MKSheppard** » 2005-03-08 07:06pm

This needs to be affordably priced. A $50 dollar add on is about right. They need to cut the memory down though, 128 MB for physics alone?

phongn · Post by **phongn** » 2005-03-08 07:55pm

A PPU might not give that good a boost -- physics engines are fairly general purpose things (as opposed to the more specialized and highly parallel instructions used in GPUs). You'll also have to write physics code for it.

White Haven · Post by **White Haven** » 2005-03-09 01:06am

Physics and AI, the two big CPU-killers. I'd kill for a dedicated PPU, and an AIPU to boot...I'm tired of games being dumbed down because one or the other can't be handled in large quantities. Look what happens with the Source engine if you stick a shedload of Combine in a room with a load of rebs? It runs fine...unless you turn full AI on. Then they all try to move...and the AI calcs bring the game down. Try Halo multi-explosive fratricide and watch the game choke. This sort of thing is NEEDED.

Pu-239 · Post by **Pu-239** » 2005-03-09 01:37am

Well, dual core CPUs may help the situation... but may be annoying to program.

Dahak · Post by **Dahak** » 2005-03-09 03:33am

Pu-239 wrote:Well, dual core CPUs may help the situation... but may be annoying to program.

But most games aren't written to make use of multi-CPUs and run multi-threaded.

Arthur_Tuxedo · Post by **Arthur_Tuxedo** » 2005-03-09 04:50am

Today's HardOCP talks about Intel's efforts to change all that. Intel just might have the clout and resources to develop the necessary tools and get them adopted quickly, but time will tell...

Arrow · Post by **Arrow** » 2005-03-09 09:52am

Arthur_Tuxedo wrote:Today's HardOCP talks about Intel's efforts to change all that. Intel just might have the clout and resources to develop the necessary tools and get them adopted quickly, but time will tell...

The latest Intel compilers already have the ability to detect code that can be run in parallel on two different cores, and compile to the code to use those cores at the same time.

Also, a coworker was experimenting with a pThreads library for Windows, and he had a single process using up both hyperthread cores.

The question is will the devs take the time to design a product that uses multiple cores. Having things truly running in parallel can create some massive communication headaches between threads.

phongn · Post by **phongn** » 2005-03-09 10:19am

Multicore designs are not some magic pancea -- multithreading is still a PITA with or without compiler assistance and there's no guaruntee that you can (for example) separate AI into its own process or thread to execute on another CPU.

Ace Pace · Post by **Ace Pace** » 2005-03-09 10:29am

http://www.novodex.com/rocket/NovodexRocket_V1_1.exe

The Gods of the net requires that you download this and watch some of the bigger demonstrations...

Words cannot describe towers made out of (probebly) thousands of bricks collapsing.

Words cannot describe the framerate drop when that happens too

Spyder · Post by **Spyder** » 2005-03-10 01:17am

A better idea would be to start sticking co-processors on graphics cards for handling AI and physics. They'd effectively just be updated versions of old math co-processors, I doubt that they'd even heat that much and PCI-Express should certainly have the bandwidth to support the additional threads.

Ace Pace · Post by **Ace Pace** » 2005-03-10 09:50am

Spyder wrote:A better idea would be to start sticking co-processors on graphics cards for handling AI and physics. They'd effectively just be updated versions of old math co-processors, I doubt that they'd even heat that much and PCI-Express should certainly have the bandwidth to support the additional threads.

The problem would be space and cost, where would you stick this additional processor? Look at the current high end graphics cards, and you want to confuse the issue more? Where is the added 128MB going to go?

Even if all that is added, price will skyrocket, far more expensive then just making a small board.

Post by **Beowulf** » 2005-03-10 09:56am

Ace Pace wrote:The problem would be space and cost, where would you stick this additional processor? Look at the current high end graphics cards, and you want to confuse the issue more? Where is the added 128MB going to go?

Even if all that is added, price will skyrocket, far more expensive then just making a small board.

Make the card longer, voila, enough space. Considering that it's mostly only going to be high end gamers who will want this, at least to begin with, tacking it onto a graphics board makes sense.

SPOOFE · Post by **SPOOFE** » 2005-03-10 03:31pm

Make the card longer, voila, enough space.

Bwahahaha!

Dude, the high-end memory cards are ALREADY approaching their size limit. A GeForce 6800 Ultra is fucking huge. It probably won't even fit in most lower-end towers. And you propose making them bigger? Ha!

Space is already at a premium. The only place to expand is... to another slot.

EDIT:

Considering that it's mostly only going to be high end gamers who will want this

Bzzt, wrong. People thought only high-end users would seek 3D cards, and they were dead wrong about that, too. The market best supports a broad range of the same product... which is why graphics cards always have low-end, mid-range, and uber-high end lines of products. The PPU will wind up much the same way.

Post by **Beowulf** » 2005-03-10 05:21pm

SPOOFE wrote:
Make the card longer, voila, enough space.
Bwahahaha!

Dude, the high-end memory cards are ALREADY approaching their size limit. A GeForce 6800 Ultra is fucking huge. It probably won't even fit in most lower-end towers. And you propose making them bigger? Ha!

Space is already at a premium. The only place to expand is... to another slot.

EDIT:

Considering that it's mostly only going to be high end gamers who will want this
Bzzt, wrong. People thought only high-end users would seek 3D cards, and they were dead wrong about that, too. The market best supports a broad range of the same product... which is why graphics cards always have low-end, mid-range, and uber-high end lines of products. The PPU will wind up much the same way.

You could also slap the PPU on the backside of the card, considering that most motherboards have the video card at one end of the row of slots.

Third solution: daughtercard sticking off the main video card.

You can get a TV tuner integrated into a top of the line video card. There's room to be had, if you try to find it.

And in case you haven't noticed, a number of video cards already take up two slots, namely that 6800 Ultra you mentioned.

And you snipped a rather vital part of the my sentence,

Considering that it's mostly only going to be high end gamers who will want this, at least to begin with

It'll be a while before the lower end users begin to see the need for it, at which point lower end versions of the PPU will be made. However, these lower end users will most likely be buying approximately the same quality of PPU and GPU.

Dahak · Post by **Dahak** » 2005-03-10 05:49pm

Beowulf wrote:[And in case you haven't noticed, a number of video cards already take up two slots, namely that 6800 Ultra you mentioned.

It only takes up two slots because it has such a huge cooler unit on its chip. I doubt it will do it good to add even more potential heat sources on the same card...

SPOOFE · Post by **SPOOFE** » 2005-03-10 06:31pm

You could also slap the PPU on the backside of the card, considering that most motherboards have the video card at one end of the row of slots.

Third solution: daughtercard sticking off the main video card.

You can get a TV tuner integrated into a top of the line video card. There's room to be had, if you try to find it.

You're right, those are indeed physically possible. But why not just put it on a separate PCI card instead avoid all that ridiculous stuff?