Computer not turning on

[35g700]

Recently I have had trouble with my computer, I would turn it on and the fans would spin for about 1/2 a second and then they would stop and all I would get was a blue power LED. At first I thought it was the video card because it would run fine without it plugged into the motherboard so I RMA'd it on newegg. Today I rememberd my I still had my grandfathers PC he had so I looked in it and found a PCI video card, I popped it in and it worked. I loaded up vista and it crashed (probibly because the video card is so old) I turned the PC back on and I got the blue power LED. I looked in my computer, tightend the RAM and turned it on again, still the blue power LED. I removed a stick of RAM and it booted I attempted to install a copy of windows 2000, when somthing with partitioning went wrong I shut it down so I would erase my HDD. I turned it on and got the blue power LED, I put the stick of RAM back in and it booted. I ran the windows memory test and nothing wen't wrong so the RAM is good. I shut it off and guess what? I got the blue power LED again, so I removed the video card, turned it on, turned it off and put the video card back in and booted to xubuntu I was going to install xubuntu on this computer but all it see's is my 500GB HDD, I restarted the computer (warm boot) attempted to load windows vista, the vista partition was good but I did delete the 55GB windows 7 partition I had.

Anways here are my questions:

1) What should I do about the HDD? I can load vista it's there but xubuntu cannot see it? Is there somthing I can use in the vista disk?

2) What is wrong with my computer? Is it a bad motherboard, PSU, or CPU? It's not the video card, or the ram because I have tried 2 video cards and I ran the memory test, I will bring the PSU into my PC servicing class tomorrow my techer has a PSU tester that will check to see if thats what has gone wrong.

anyways thanks for the help and I'm sorry if the post is a little messed up the video card I'm on only does 800x600 and the spell check in xubuntu is set to french or spanish and I don't know how to fix it

 

[King X13]

I have had this happen in 2 situations.

1) Motherboard - crappy capacitors or bad defective ones or damaged ones. When they have a problem holding a charge the pc becomes unstable and you get weird power situations like yours.

2) A bad power supply, either going faulty or got damaged in a surge etc. Or and under powered power supply. Meaning your system is trying to draw more power from it then your power supply can dish out.

It could be others but i would start with these two things.

 

[35g700]

Thanks, tomorrow I will bring my PSU to my PC servicing class and have that checked out, if its good I will probibly bring in my computer for him to take a look at, he has been working with PC's for many years and will probibly be able to spot a bad cap much eaiser then I can.

 

[35g700]

My video card came back today, (only got the card and one adapter, I sent all that came with it in and got just the card )

It still does the blue LED thing but only when I have a card plugged into a PCI or PCI express card slot to get the problem to go away I have to remove the video card from the motherboard and turn on the computer, turn it off then put the video card back in it and I can use it.

What could the problem be like bad SB or something?