I have a custom built home computer, and sometimes it won't power up, or rather start the bios. I can't figure out why, PLEASE HELP!

What do you mean it won't power up? The fans don't spin sometimes when you press the power button?

FlameNo No, I mean, my bios won't iniate.Do you have virus and Spyware protection? When did this start? Has it ever worked properly? Have you made any changes to your system recently?

FlameIf ur talking abt BIOS then it does start, otherwise how would u know that its the BIOS.
I think ur talking abt Windows not starting, the PC works right? Does it reboot or give u an error message.
I need more info to help u.Alright, it has always happened, I THOUGHT maybe it was a hardware configuration issue, but no, I tore it down and rebuilt it plenty of times.... Then I thought maybe it was a power issue, put in a new power supply, nope didn't work.....And Guy I know it's the BIOS because the BIOS DOESN'T Load.....thats just it, every other time, I turn on my computer, my BIOS, does not load, I get NO action from my computer, the CPU monitor light flashes, the harddrive lights flashes, the CD ROM doesn't and my Monitor doesn't acknowledge the computer being started. No reboots, no error messages, NOTHING, point blank, I get NO action....I even used my Mother board's Error Reporter to try and figure it out. Still nothing, I should TELL you all, I have a 939 board. PCIE x16 slots, Sata Hardrive, and Dual Core Processor.I am truly amazaed at the amount of info here that was NOT included in the original post!!!You guys really aren't very helpful....If my computer wasn't down at the moment (I am in the process of reformatting the OS...it has nothing to do with the problem at hand) I would give you guys all my system info.We try to be helpful, but it helps to have all pertinent info at theoutset. If you are formatting the drive, you are beyond a non-functional BIOS.Wow, I give up with you people, The Formatting has NOTHING to do with the hardware issue, I think I will just sit down and figure it out myself, thank you though. Circles are quite fun to run around in.The on again off again bios, I think you have a hardware problem and my money is on the psu.
Do you have total CONFIDENCE in the size & QUALITY of the new psu you put in?
Everyone here is really trying to help you.I'm with Fed. In diagnosing an intermittent startup problem, I would strip the PC down to its core, and try to boot several times, with as few things connected as possible. Then repeat with a different graphics card. Then with different memory configuration. Then with different processor. Etc.