computer cannot startup

[sentme_mail]

hi,
what could be wrong if you press the power button, the computer starts to load BIOS and shuts down by itself?

 

[Paithar]

Just a thought but it might be your power supply. Does it give you any kind of POST test (any beeping at all)? Are you able to go into the setup(bios/cmos whatever you want to call it)?

You might want to make sure that everything is seated correctly on the motherboard and that all power connections are good.

 

[sentme_mail]

there's no beeping sound on startup.
i am suspecting mobo or power supply problem, but how to confirm it?

 

[z-lite]

Does anything come on the screen? Is the CPU's HSF plugged into the right connector (some motherboards won't start up if the CPU fan is not spinning/has a low RPM count)?

 

[Paithar]

Probably the best way to test either the motherboard or the PSU would be to try a different one if you have it. I don't mean rush right out and buy another PSU and/or motherboard because it's possible that neither of these is the culprit.

If you have an extra PSU (like in another pc) then I'd first swap the two and try that. If you're still having problems you might stripping everything else out of the system except what you really need to start up. In other one stick of RAM, one hard drive, video card (if your mobo has integrated video you might try that just to rule out the video card). See if it'll start up with just a bare minimum of pieces.

Btw, what is the system specs and have you changed anything lately in this system?