** Opinions Required On My New Rig **

rapid1:

All I know is you have to have PhysX to run DAO

I believe you.  The thing is, if you install PhysX without an nVidia GPU, it falls back to CPU-only mode (which performs relatively poorly compared to the hardware accelerated version).  The CPU train of code is not at all optimized, probably purposely, so as to make the nVidia hardware 'more valuable' for games that use PhysX.

realneil:

But that is with the caveat that you have to have an NVIDIA Card installed too, and it has to be the one that does the PhysX processing

Yes.  GPU's are like CPUs:  Each manufacturer has their own set of opcodes.  Running the nVidia PhysX code on an AMD/ATI card would be like trying to run x86 software on a PowerPC CPU...  They literally speak a different language.

The only way to run PhysX or CUDA code on an ATI card would be to write an emulator that converts all the operations to those of the host card.  it would be incredibly hard to do (because of the widely varying capabilities of all the GPUs), and add a significant overhead.

This proprietary implementation is what makes the alternatives like OpenCL so attractive.  As an intermediate interface that's supported by both manufacturers, you don't have to write your code twice.

No actually when I ran it it was ran with my CPU. My I7 did not have any issues with it. Of course with 8 available threads that kind of stands to reason. So I ran PhysX against the OC'd I7 rather than the GPU (5870 or 5870/5850) and ran everything to highest detail without a hitch. From what I understand if you have an Nvidia car it actually runs combined between the GPU and CPU anyway. As I said though I had absolutely no issues, and everything worked fine on highest detail.

I apologize about the responses before, but I did not really think about it to tell you the truth. The graphics were coming through my GPU so I did not really think about it. Everything ran fine though on full detail which led me to believe at the time that Physx was and is pretty much a rip off as a singular application thread, and or reason therefore to buy an Nvidia card for it. Because it ran in combination between my GPU and CPU without issue or flaw, and my GPU is an ATI. So if a current processor has more than enough power ( I also ran it on Sarah's 965 black equipped system with no issues), and everything looks great on highest graphics detail why would I or should I spend the extra money to get it?

Some games look a lot better with PhysX installed and running on the GPU. I don't know if it goes to how they're coded, or if they have a heavier implementation of PhysX within the game. How it works doesn't interest me as long as it works.

I do know that if I go to my NVIDIA drivers settings and choose to render PhysX with the CPU, (i7-870 running @ 3.93GHz. speed and 8GB of DDR3-1600 RAM) It looks like crap and is jerky as can be. But if I go back to my drivers settings and choose to render PhysX with the GPU, It works perfectly and at high detail. I have a GTX-285 2GB, a GTX-570 1,280MB, and a GeForce GT-430 1GB that all do PhysX and CUDA nicely.

It happens exactly the same with my other i7-870 system. (running @3.8GHz. speed and 8GB of DDR3-1600 RAM)

It happens the same with my i5-750 @ 3.8GHz. system with the same RAM in it too.

My Radeon HD-5850 and my Radeon HD-6870 don't do it at all. The effects just aren't there.

Go Figure,.............

rapid1:

I apologize about the responses before

No need!  We're all here to share, and we all learn from each other.  You're cool in my book.

To tell you the truth, I think PhysX is overrated.  I think that's why their original model, where they had a separate PhysX card failed.  So, I agree with you:  The hardware acceleration just doesn't make that much of a difference in most games - unless the rest of your system is anemic.

PhysX is a bit over rated like 3vi1 says. Some games use it well, others dont. I say if you have a Nvidia crad enjoy it. If you run an ATI card dont worry about it.