My computer won't boot, please help

[Newbie91]

So first off, im sorry if this was in the wrong section, im new to the forums. This is a computer I just finished assembling today (so I thought homebuilt would be appropriate).

So...When I click the power button on my computer this is what happens. I hear the noise of the hard drive turning on, the optical drive responds and will open, and the CPU Fan will spin once, then everything shuts down. Nothing ever appears on screen.
Does anybody know what the reason could be? ie: bad cpu, psu, or mobo perhaps?
Any help would be greatly appreciated, thank you.

 

[Marmour]

i would get your psi checked out, they sell checkers, so go buy one. It's probably not the mobo because it wouldn't turn on at all but i think its the psi
try a friends psu

 

[Newbie91]

Oh an in case anybody was gonna scold me, yes I ran through the troubleshoot page already. That's why I posted here.

Marmour, thank you for the opinion.

 

[Marmour]

Oh an in case anybody was gonna scold me, yes I ran through the troubleshoot page already. That's why I posted here.

Marmour, thank you for the opinion.

no problem man, just happy i could have been of assistance.
if you need any more help just message me, cheers!