It would also help to know how many Hardrives you ar running, Disk drives and any peripherals you have becuase i could say that CP uses X amount of watts but that wont accountfor everything in your system. Most Power supplies devout 1/4 or so of the wattage to the power supply and motherboard. And off the top of my head i think the Athlon X2 uses about 80-90watts. And all power supplies have Molex connectors unless you built yours from sap and sticks. If the Video card needs a the mid-upper PSU's come with them and you can get a converter. And i asume when you say your PSU you was a tagan420 that means 420watts so id try a powersupply with 500+watts or maybe the tagan had an low rating on the 12V rail. But just for myself what lead you to believe it killed your PSU? doesnt turn on,machine wont boot?