I have that same computer from dell. The dell forums claim you can use any ATX power supply. Just make sure it has at least 4 SATA connectors. I'm looking at the OCZ modular ps, I think it is the 600W at Newegg. I'm considering a 9800GTX+ video card, which has been used successfully in an Inspiron 530, according to the forum. Good luck and post what you wind up with. I'm a few months out from an upgrade, so I'll be interested in seeing what you get.
