PPU Concerns - Slower framerates?

DejaWiz

DejaWiz

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Will the use of a PPU actually slow down framerates in a game/app that can utilize it? I was just concerned because all those extra particles and whatnot still have to be rendered. Won't this be putting more demand on the GPU?
 
actually i think its the cpu that will allocate what particles to be rendered and junk. so me thinks if one have dual core cpus, should be fine...


then again i can be totally wrong
 
yep, you are wrong, the whole idea is to offload all that stuff from the CPU


with more objects on the screen yes they will have to be rendered, for example lets say it produces more alpha blended particles, the GPU will have to render them
 
Brent_Justice said:
yep, you are wrong, the whole idea is to offload all that stuff from the CPU


with more objects on the screen yes they will have to be rendered, for example lets say it produces more alpha blended particles, the GPU will have to render them
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So an increase in alpha blended particles and the like won't put more stress on the gpu if a PPU is present and being used?

In essence, will having a PPU neccessitate the need for a high-end GPU?
 
I personally have not played a game using physics acceleration (but I've seen the videos live). It makes sense to me that the PPU will create more objects in the world that the GPU will have to render.

I think the only way we are going to know how it effects perf is to try a game with and without a physics processor.
 
given a little time i think the ppu is gonna ask sli/crossfire to put its money where its mouth is...
 
DejaWiz said:
So an increase in alpha blended particles and the like won't put more stress on the gpu if a PPU is present and being used?
Click to expand...

Yes, to some degree. The basic argument is this. In current titles, high-end video cards are bound (waiting for) the CPU to finish what it is doing so that the GPU can render the next thing. A lot of what the CPU is struggling with is the calculations related to what hits what where, what happens after that, etc. All the physics stuff - what happens if someone shoots a hole in that brick wall, how big is the hole? Does the whole wall fall down? where do the bricks fall? Does any of the shrapnel from that wall hit anything else? What happens if it does?

The PPU is designed to take care of all the "what if's" in my example, which lets the cpu spend more time managing the results of that, calculating AI, and things like that. Yes there will be more stuff for the GPU to render, but the GPU is already really good at doing that, and so shouldn't have much problem rendering the extra pieces.

 
I really hope that high system requirements will not be a downfall of the PPU.

It dawned on me that when PPU-enabled games come out that are as demanding (if not more) as FEAR or Oblivion with quadruple the particles and effects would mean some nasty slow framerates for a majority of users without a high-end GPU or Crossfire/SLI. We'll see once the time comes. I just hope that almost everyone can benefit from a PPU, not just those that have dumped a pretty penny into their graphics card setups.
 
Brent: I'd be really interested to see how well PPU-enabled games and apps scale with different GPU's. Do you and [H] crew have any plans to do a full PPU review using a vast array of GPU's from all the price brackets?
 
DejaWiz said:
Brent: I'd be really interested to see how well PPU-enabled games and apps scale with different GPU's. Do you and [H] crew have any plans to do a full PPU review using a vast array of GPU's from all the price brackets?
Click to expand...

Nothing is planned now, but you never know.

I see great potential in physics processors, I am definitely excited about evaluating what they will bring to the gaming experience.
 
Another thing to consider with a PPU is that it is possible that we will move from a few large complex physics objects to many small and simple physics objects that make up a new destructable object. Although there will be an increase in objects, the total number of polygons that need to be rendered may not increase proprotionally to the number of objects being simulated.

Time will tell...
 
I thought the whole point of the PPU was to speed things up, not to make it a fricken requirement to have SLI/cross fire.

This is all so depressing. At the rate this is going my hobby of computer gaming is fast becoming very unaffordable.

Back in the day when I bought my GF4 4400 I managed to make it last for a whole 3 years. I bought a GF6800GT last year and it already has troubles running game at full details on 1024x768.

Maybe ill just buy an Xbox 360 :(
 
Yes and No

Take away Physics from the CPU is a Big plus

But if it means we're doing cloth deforming, massive ammounts of objects, particles and fragments of objects. We increase the rendering load.



All in All i can't wait to see what comes of it.
Hell if they made a addon solution that only did AI work id get that too
 
defiant007 said:
I thought the whole point of the PPU was to speed things up, not to make it a fricken requirement to have SLI/cross fire.

This is all so depressing. At the rate this is going my hobby of computer gaming is fast becoming very unaffordable.

Back in the day when I bought my GF4 4400 I managed to make it last for a whole 3 years. I bought a GF6800GT last year and it already has troubles running game at full details on 1024x768.

Maybe ill just buy an Xbox 360 :(
Click to expand...

id wait to see numbers before i would discredit it.
 
I would think that redering a few extra polygons would be nothing compared to the calculations that the PPU will take off of the CPU.

Think about it. For an object, the GPU has to figure out:
What shape is the object?
What texture does the object have?
How do I apply AA and AF?

Whereas a PPU has to figure out:
What is the size of this object?
What is the mass of this object?
What is the velocity of this object?
How are these factors affected by wind and gravity?
What potential force does this object have?
Will this object collide with anything else before falling to the ground?
If so, what will it hit?
Will it have enough force left to damage whatever it hits?
How much damage will occur?
Will the object be shattered on impact, or will it go through the object it collides?
 
HOCP4ME said:
I would think that redering a few extra polygons would be nothing compared to the calculations that the PPU will take off of the CPU.

Think about it. For an object, the GPU has to figure out:
What shape is the object?
What texture does the object have?
How do I apply AA and AF?

Whereas a PPU has to figure out:
What is the size of this object?
What is the mass of this object?
What is the velocity of this object?
How are these factors affected by wind and gravity?
What potential force does this object have?
Will this object collide with anything else before falling to the ground?
If so, what will it hit?
Will it have enough force left to damage whatever it hits?
How much damage will occur?
Will the object be shattered on impact, or will it go through the object it collides?
Click to expand...

Interesting point but...

Your GPU example is way over simplified.

and most of the stuff you list as PPU features are not being computed on the CPU currently, so computing them on a PPU won't lead to a reduction in CPU load for those features.

Comparing GPU loads to PPU loads and how they affect the CPU's load is a HUGE topic. A very basic treatment of the subject would probably require a minimum of a 3 to 4 page document. An in depth evaluation would be a 100 page book.

There is a very large difference in the amount of computing required to do the different operations that you list, so just a list of operations is a misleading way to frame the subject. I wish I had the time to give a little larger explanation.
 
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