Basically I have a hand-me down computer from a friend because my own stopped working and I'm still saving up for a new rig. It's been working fine for a while now, but last week or so the fan on the graphics card (GeForce 9500GS) stopped working.
DO NOT GET THE GT640!! Get the HD7750 its the same in performance as the GTX650 but smaller and more cost effiecient. And yes it will work + The HD7750 doesn't need much power. 50w at max load.. and draws all its power from the pci express slot. Yes its just a matter of plugging it in