Computer is Receiving Electricty but Won't Power-On

Yesterday, when I left for work, my PC was up and running. When I came home, it was off. I pushed the power button and NOTHING happened. No fans, no lights, no sounds. I opened my case and checked the physical connections and all of them are soundly connected. The computer is a custom build a little more than a year and a half old.

On the motherboard, there is a little, green light that is actually on and goes off if I move the power switch in the back of the PC to the off postion and goes off as well when the computer is physically unplugged.

 

Disconnect from the AC,flick the power on on the PSU,press the power on button to drain any residual current.

Find the cmos battery "Shaped like a silver coin" and remove for 20 secs then replace,reconnect to the AC and try to power up.

If this doesn't work,disconnect disk drives,add in cards,remove all memory but one stick in slot 0 and try to power up,then try with another stick.

If this doesn't work I'll describe a PSU test.

 

Regrettably, I think we're at the point of a PSU test.

 

Remove PSU from computer "You can skip this and just remove the main motherboard connector but its safer this way" get a paper clip and bend into a 'U' shape and connect the green and ANY black wire on the end of the main motherboard connector,the psu should fire into life signalling working psu,for further piece of mind test the voltages on the main motherboard connector with a multimeter.

http://www.google.co.uk/imgres?imgu...y=101&sqi=2&page=1&ndsp=18&ved=1t:429,r:0,s:0

If your not confident doing that PSU tester can be bought for a few bucks,there are also videos of the procedure on youtube of your unsure.