Im not an ATI fan so no 5XXX card, yes i plan on play physx games, no i dont have a extra card lying around.
Ok, so you're not an ATI fan. Very few people are. That doesn't mean that you can't open you're eyes and see that ATI is the better buy right now. You're realy better of seling that GTX 275 on Ebay, for about 200$, maybe more, and saving 100$ for the PhysX card. that gets you 300$, wich is enogh to upgrade to a 5850. Or you could throw another 100$ in there, and buy a 5870. Give me a good reason why you don't want to buy ATI now. And no, you don't use 3D vision so you can't say that. And PhysX isn't comparable to the huge benefits fo the 5850/5870 has over you're card.