GTX 580 and Mafia II Physx= low fps stuttering

[JumBie]

So i have an MSI GTX 580 OC TWIN FRZR II, and i have Mafia 2 running at 1080p with all settings on highest.

With Physx on high, i get noticeable stuttering and frame rate drops to the point where i forgot why i even payed for a 580. At medium its the same but slightly bearable.I have vsync on, and i notice with physx in certain outdoor, indoor, and random areas i get stuttering and big fps drops sometimes down to the 20's and 30's. When i take physx off completely i get no stuttering and no fps drop, i remain at a steady 60fps with vsync on.

Does anyone else experience this, or is it just me? Because i gotta say, i thought physx was made for nvidia, and a 600 dollar card, is clearly not doing this game justice.

 

[(sic)Klown12]

You're asking the card to do two demanding things at once. You have it rendering the scene in high detail plus putting a fairly demanding load with Physx. Even the GTX 580 has it's limitations. If you want to keep Physx on and at high with no slowdown you're going to need a second card dedicated to it.

 

[SunnyD]

You're asking the card to do two demanding things at once. You have it rendering the scene in high detail plus putting a fairly demanding load with Physx. Even the GTX 580 has it's limitations. If you want to keep Physx on and at high with no slowdown you're going to need a second card dedicated to it.

Not really... PhysX shouldn't take more than about 10% of GPU's processing power, especially on a GTX580. It's been shown that in most games, the performance hit that PhysX makes on a single card setup is negligible. My question for the OP is what are your frame rates with PhysX disabled. My guess is that there's something else at play, like an underpowered CPU or lack of ram in the setup.

 

[(sic)Klown12]

Mafia II makes better use of Physx than most games(I can't think of one game where it's been implemented better). When you get into firefights and have debris raining everywhere it creates a large load on the GPU, first with all the calculations and then rendering the effects. I've played it on a system with a GTX 480 and saw the same dips that the OP is mentioning, but down to the teens at the lowest. Turning the Apex setting down to medium will help some, but there will still be noticeable dips in the framerate.

 

[JumBie]

i5 2500k at stock speed
8GB mushkin 1333mhz ram
120gb Vertex 2 SSD
GTX 580
850w Corsair TX

Thats my setup, i figured the 580 would be more than sufficient to run mafia 2 with physx with no problem. Like i said i play with vsync on to keep the screen from tearing. Without physx i get a constanct 60fps all the time, and everything is perfectly smooth. With physx on medium i get 60, but it fluctuates from 50-60 and drops even lower in certain outdoor and indoor enviroments, the same happens with high physx, alot more often though.

I understsand some might think that i need another card to run physx on mafia 2, but I've seen my buddy run this on a 480 same settings high physx with no problems at all.