PhysX on GPU or CPU with SLI?

[youpla]

Title says it all... I have checked what's out there on the net and I am still confused as what is the best option.
After activating SLI mode in nvidia control panel the default setting for PhysX is set to use CPU.
Although it seems to be recommended for single card, I wonder if it would be better to switch PhysX to GPU in SLI mode?
Any input or advices would be more than welcome...

 

[MadMarc]

I guess it's better if you use the cards in SLI, check this video out: http://www.youtube.com/watch?v=cbww3dhzK0M

 

[SmoulderingCircuits]

I'd stick with CPU unless you have a really slow CPU or you have a low-mid range card to sit alongside the SLI cards for dedicated physX.

 

[Rastalovich]

If it's your 670 SLI setup. PhysX on the SLI, it'll deal with it like a hot knife through butter.

An additional GPU or CPU use will hamper the performance.

 

[SmoulderingCircuits]

If it's your 670 SLI setup. PhysX on the SLI, it'll deal with it like a hot knife through butter.

An additional GPU or CPU use will hamper the performance.

Is it more work siphoning off the physics to a dedicated processor than it is to leave it where it is and process it at source (so to speak)?

 

[youpla]

Thanks guys, i'll switch PhysX to the 670 SLI then!