I've got a Gateway FX530XG. The Spec's say I have one x16 PCI Express slot but it doesn't say weather it is 2.0 or 3.0. It also say's that I have three conventional PCI 2.3 slots. I would like to know If I buy a G-force GTX 650 ti card that is a 3.0 card will it work or should I buy the G-Force GTX 560 ti card that say's its a PCI Express 2.0 card.
yes you can put a 3.0 in a 2.0 slot but it will run at 2.0 speeds. its backwards compatible.
Also, keep in mind... there's no difference yet between 2.0 and 3.0 speeds. You will see NO difference between a 650ti in a 3.0 and one in a 2.0.