So, I've read the 2010 article on this from Tomshardware.
And it got me thinking that it would be possible to gain performance and eye-candy in PhysX supported titles.

I'm a happy AMD owner of two 6970s in a crossfire setup, and want to expand my gaming future by trying to get PhysX to work.
Of course it works in some degree with those powerful cards (Metro 2033 is actually quite playable when physX is enabled), but I would like to be able to use the 6970's graphical capabilities along with nVidia PhysX for eye-candy.

The article goes that if you install nVidia drivers, it should work...
Simple as that, and you should be able to get positiv performance with nVidia driven PhysX, versus CPU-driven PhysX.

And of course, the more powerful nVidia card you have, the more would you actually benefith with this kind of solution.
But I'm planing on getting the entry level GT 610 PCI version.
It's not like I've vasted a lot of money if I choose to buy it anyway. 

So, am I an complete idiot thinking that this would work or would it actually be possible?

You won't get it to work in any modern game either, since nVidia has since moved to a new PhysX SDK and doesn't work with the older cards which support this (such as the GeForce 9800 derived cards). It's also not worth it, since most games are moving to cross platform PhysX such as DirectCompute, Havok, and OpenCL.

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Its possible, but you can't use any nvidia drivers, you have to use very specific ones, old ones where the exploit hasn't been fixed yet and modded physx drivers.. and even after that you will NOT be getting it to work in all games that have physx and usually it can be enabled via ini file tweaks etc. An entry level nvidia gpu is all you need if the only job it will be doing is physx. Expect crashes, bsods, errors in every direction as this thingie is not meant to work like this.

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