Re: PhysX Card w/ My GTX 460
I would lean towards the 9800GT.
The 8800GTX I myself would count out for heat reasons.
Any of those should work quite well though.
MSI Z68 G3 | 2500k | CNPS9900MAX-B | 8GB G.Skill | EVGA GTX760 |ThermalTake 850w | X-Fi Titanium | HAF | Asus PA248Q | Lycosa | Death Adder | Win8 Pro 64
Asus P5QL Pro | Q9400 | H50 | 8GB G.skill | GTX570 | Ubuntu 13.04
17" Inspiron | i5 | 4GB DDR3 | 500GB HDD | Win7 Pro 64