I'm new to hardware work, so this might be a stupid question, but how can I tell if a new PSU will be compatible with my other components? I have an Asus M4A78LT-M LE motherboad and I'm looking to upgrade my current 450W PSU. I got a Visiontek ATX 650W psu (http://www.compusa.com/applications/SearchTools/item-de...) and conncted it to everything (including the 24-pin and 4-pin Mobo connectors, but the PC wouldn't even turn on. I'm petty sure I didn't make any connection mistakes, since I was able to put the old PSU back in and it booted up fine.
I would really appreciate some advice
P.S. I have an AMD Atholon II x4 635 cpu and an ATI Radeon HD 5570 video card .
Every couple of blue moons you run into a situation where a specific PSU won't work with a particular motherboard, but as a general rule any ATX PSU should work with any ATX motherboard.
Since the old PSU works, and the new one doesn't, my initial thought would be that you managed a bum PSU and should send it back for a replacement. If the replacement does the same thing, then we need to look at other possibilities.