My pc died last week, just stopped working, for no apparent reason. No power at all to the pc. I looked inside and there is a little green light which is lit on the motherboard, all else is dead. MB asus P4G8X. 2.6 gig intel processor. I am running xp. I did some reading and decided to buy another power supply. I even got a larger one for future use. Installed it today and nothing same old, same old. All is dead except for the little light on the mb. I took the old power supply and plugged it in and checked voltages at the leads and I can read nothing. Should there not be voltage there? Providing this is a good ps. The fan doesn't even run. Should not the fan run??? How does one check the power supply? I am wondering now if the ps I just purchased is bad? How does one check the power supply? I am wondering now if the ps I just purchased is bad? Could the mb be bad and is there a way to check it? I need some help please. Ray

The green light on the board indicates that it's receiving the 5v Standby power, but that doesn't necessarily mean the PSU is good. To benchtest a PSU, you have to connect a jumper wire between the green & any black wire, then you can check the voltages. What make/model/wattage PSU did you buy?

I got an Apevia Win-500xspx 500w R I am going down and look for the green wire now. I am really curious to check those voltages...

http://www.google.com/search?hl=en&... Good tool to have handy. They'll save you money and frustration over the long haul.

I got a question about which green wire to use. does it make a difference? My 20 pin connector is the only one with green wires and there are several...

http://www.google.com/search?hl=en&... I think your answer is here?

Apevia PSU's suck. The green wire is the "power on" wire. To steal a line from Highlander..."there can be only one!" http://pinouts.ru/Power/atxpower_pi... Checking the voltages is only somewhat useful. What you'd really need to do is test the amperages under load, but that ain't gonna happen. Just so you know, the ATX specs allows for a 5% +/- tolerance on the voltage rails.