power supply/6600Gt help

[PTgamer]

Have been researching extensively, and as a part-time gamer playing CoD, Civ4, etc., have come into possession of a mini-tower w/ P4 2.4ghz, 760mb ddr. Looking to set it up for ipod, games, and camcorder, I decided on a budget minded 6600GT card. Until, that is, I realized this former corp. business computer was given only a 250w power supply! I need a 350w w/ molex to run the low/mid level 6600gt. My question is this: I cannot find an online source that provides an upgraded power supply that I know will fit. I also worry that the mini tower won't offer enough airflow to cool a bigger power supply. Can I do this upgrade, (at about $300 for ps and card, or am I better off spending $1000 and getting a new computer?) I use a 5200fx on my old P3 700mhz 310w power supply, and it works ok- is there a lower level card that will handle T&L and shading w/o the current power for the mini tower?
Thanks guys

 

[Rugger]

6600GT will be a significant upgrade from the 5200fx.

You should take the measurements of the PSU bay from the case and then check on a site like Newegg for PSUs - they have pics and dimensions. This FSP 300W should do you justice if it fits.