I am upgrading my machine and will be getting a 660ti/560ti. I will have a leftover gtx260 will there be any advantage to using the 260 as a dedicated physx card? I have a pci-e 3 board so dropping the main card to x8 should not be a problem.
The GTX260 is plenty fast enough run all the physx for any game out there. The question is what games are you playing that use physx? In a game like Arkam the 660ti will run on the highest settings with physx with no problem. Off loading the extra over head of physx may get you an extra 5 or 10 FPS but if your already at like 70-80 then its not really much use.
In my case if I turn off sli and use 1 470 for games and 1 470 for physx the games looks and plays exactly the same.
In short the gtx260 will work fine, I think you should try and see if you get any noticable fps increase.
I only have like 3 games that support physx, so i dont really see any value in it.
"physx" is an Nvidia proprietery tech that "supposed to allow rendering of realistic physical interactions of objects in the game" and this is pupposed to happen using less resources then a video card would normally use - so the result is therefore a higher framerate in your game.
Does it REALLY work like that? well yes, but the framerate we are looking at is a gain of like 1 or 2 frames while making your game supposedly "looks better" I never noticed a visible difference with it. I really think its more of a marketing gimmic for NVidia then a tangible SIGNIFICANT improvement that I can measure.
why would a developer incorporate something that at best 60% of the market can use? unless of course you drop a suitcase full of money on their door step. i would personally sell the GTX 260 while you can, help cover the expense of the 560ti/660ti.