PhysX Benchmark on a hybrid system

[Phixsator]

Well i have been searching Google dry forever to answer several things before i went out and bought a nvidia card to be used as a dedicated physX Card with my Sapphire 7950(for games like Borderlands 2 and Batman). Would it even work without issues in a hybrid setup? how good would the card have to be to be able to handle the latest and greatest with as little performance loss as possible? How does overclocking the card affect the physX performance? What about the amount cuda cores?

While there are plenty of benchmarks, i feel most of them are rather useless or does only test in a pure nvidia enviroment. So for that reason i went out and purchased a gt 640 and are going to bench it against a XFX gtx 260 BE. The bench will including OC of memory, core and shader clock and most of all in a hybrid system using a 7950 as the main render. It will also contain, if i can make it happen, clock for clock test between the 2 nvidia cards.

The GT 640 should arrive tomorrow and the gtx 260 benchmarks are 80% complete as of this post. With a bit of luck if time allowes it i will post everything in this thread tomorrow night.

Feel free to include any request or idea's or thoughts. There seem to be a lot of misinformation on this very subject. The point of this thread is NOT to determine if its worth the money but more if its even reliable and to contribute to this awwsome forum i've been enjoying for years as a passive guest.

UPDATED 11 October 2012
PhysX Benchmark Spreadsheet on GOOGLE

 

[Phixsator]

The reason behind why i chose the 640 gt is based on the number of cuda cores alone and the core speed. So fare using fluidmark the OCing on my gtx 260 showed a rather unimpressive increase in physx SPSon both shader clock and memory clock and while Core Clock OC yielded not much more it was still the best place to gain physX performance i fluidmark.

 

[Phixsator]

I found raw clock speed makes negligible difference. I have a custom profile which runs the 480 undervolted at 500mhz core. The difference between that and stock was only about 5fps obviously there will be a cliff somewhere but I've not found it with my limited testing.

Interesting. I to did underclock but i did not lower the volt. Results were as i expected less SPS (FPS)

 

[Phixsator]

I do own Metro 2033 and are planning to test it as well. During testing in Batman Arkham City a gtx 260 would be enough as a dedicated physX Card but not when it comes to borderlands 2, got horrible low fps in that game if PhysX was set to medium or above.

Im just sitting here yelling at the postman i cant see to come and deliver my package so i can start some serious benchmarking hehe. I want that gt 640 NOW!

 

[Phixsator]

Your not going to notice anything I imagine as PhysX doesn't use much of the core at all.

Actually during borderlands 2 playthrough some area my dedicated GTX 260 physX Card would spike through 60% usage only doing physX calculations..

On another note i think nvidia is trying to push some changes to how heavy the physX is implemented in some games. They want sales which is logically which is why we see in games like borderlands 2, Batman arkham city that a dusty old 8800/200 series Card wont be enough anymore. It could be driver manipulation on purpose to slow down performance or just the sheer number of calculations gone thrugh the roof. Neither would really surprise me. I've never had anything against nvidia ( i use to run 2 gtx 560 ti and love them dearly) but their physX business has always been shady *looks at an PPU Card from ageia and crys*

 

[Phixsator]

Well ive just done a quick bench of the GT 640 in fluidmark at 60k particals and so fare it doesnt look good . Looks like its roughly 25% slower than the gtx 260.

 

[Phixsator]

Well had a bad feeling about the last bench and decided to reinstall the entire system and start over on a proper platform (win 7) and its already looking better and makes more sense

 

[Phixsator]

Finaly the first batch of tests are done. Lost 6 hours of work due to BSOD and a corrupted spreadsheet but here it is as promised. The link is in the OP which has been updated.

 

[Phixsator]

Thanks OP seems the GTX260 is the card to be using from your tests. Have you got Borderlands 2? If so how does it perform on that?

Yes i have BL2. Problem so fare has been every test has been suffering from minor stuttering, small enough so the FPS counter wouldnt catch it but big enough so it annoys me. Borderlands 2 is even worse in this regard. Running some of the tests a second time straight away reduced the stuttering which would to be suggest i have some sort of caching problem somewhere in my system. Disabling hardware physX removed all stutter nomatter what test i ran.

Also found that using the dedicated PhysX card in a 8x PCIe 2.0 lane would reduce the performance with 20% roughly over a full speed 16x PCIe 2.0 lane. Same result on my older gigabyte x58-ud4p motherboard. I find that really strange.

 

[Phixsator]

A little update: The overall feel from actual gameplay was better on the GT 640 in both Batman and Borderlands 2. Going to do some proper comparison after i get home sunday.

Also you dont want to use any sockets for your physX card thats running off the soouthbrigde, Causes a good deal of slow down atleast on my rig.

And last regarding lag/stutter issues in Borderlands 2. Ive found that gearbox has done something to the physxcore.dll that they are using.. Using that, my CPU was able to go through bloodshot stronghold on medium setting almost all the way through(slow downs to 20 fps was seen in the big whirlpool area and a few other places). Now since im on a hybrid system i cannot use that physXcore.dll that comes with the game because it disables GPU acceleration and if the game uses ANY other physxcore.dll than what was shipped with the game the performance is tanking or stuttering regardless of being powered by the CPU or the GPU.

 

[Phixsator]

@Phixsator,
I asked earlier, and you never replied, is there any way to give me a save for the heavy PhysX areas in B2?

So sorry about that. Must have overlooked it. Here you go

https://docs.google.com/open?id=0B0zUB4Ihwv5sLVVlQTJJSWg3RlU


I actually think the GT640 is more than plenty as a dedicated PhysX but i cant test it for sure since im not running a pure nvidia enviroment. The PhysXcore.dll shipped with borderlands 2 has been modified a lot and im sure of this because its the only PhysXcore.dll that will give you playable fps running PhysX on medium and on the CPU. My guess is still that if i were somehow able to get hardware acceleration using that dll on my hybrid system the GT640 would truly shine.

I've had a short look on the hybridiz patch that most seems to be using and while it works i find its methods a bit bad to be honest. The old PhysX Mod 1.05ff would patch your files which is what we want since we get to keep any optimizations done. The Hybridiz seems to just replace them with prefixed files which is why it always works cause the files are always the same. This IMHO is extremely poor done and not what we want to use since the software is changing all the time and 3rd party developers are using custom physX files for their games which is thrown out the window with this patch for those of us using a hybrid system.

 

[Phixsator]

I'm not sure about that. The 640 does not have all that much power. As an example, Batman AC suggests a dedicated 460 for the best results with high PhysX. That is more power than what a 640 can bring to the table. Plus like I have said, B2 has hit 50% use of a 480 in certain areas. That is probably more than 50% use of the available compute power as the most use I can force out of Fluidmark is only 68% no matter how many particles I toss at it

Well as i see it if thats the case then fluidmark if not also borderlands 2 should bottom out the GT 640 which it doesnt. In Borderlands 2 the highest GPU use was roughly 62% and in fluidmark 78%. Also the stutter issues then i have reported usually happens when the GPU (GT 640) isnt even taxed that much which would indicate that its not even related to the power of the GT 640 in the first place.

Also been playing a bit of Batman Arkham City and it so fare has worked just fine no stutter at all.

EDIT: Found this thread http://www.evga.com/forums/tm.aspx?m=1756420&mpage=1

 

[Phixsator]

didnt read it through just found it and thought i'd share it for some light but apparently bad reading

 

[Phixsator]

Been playing through most of borderlands 2 with physx on medium and after the bloodshot stronghold everything runs perfectly fine on the GT 640. There have been times where there were fluids, particles and vortexs all over the place and way worse than anything shown in the stronghold and no lag what so ever. So fare all the stuttering issues ive had have been in the beginning areas of the game upto stronghold and after that it goes away weird enough.

UPDATE 26.10.2012
After the latest patch i have no stuttering issues using hybrid physX with a gt 640, not even in bloodshot stronghold.