Computer won't turn on

[qpete]

I have the power switch, reset button and the HDLED all in the right spot and when I turn the power on in the back on the power supply all the fans turn on and the light on the mother board, and the two on the front turn on but when I press the power button nothing happens. Please help!

 

[Guest]

Make sure you've installed the hard drive, graphics card and memory correctly.
Have you applied thermal paste on the bottom of your processor fan?

 

[qpete]

Make sure you've installed the hard drive, graphics card and memory correctly.
Have you applied thermal paste on the bottom of your processor fan?

Yeah I've done all that. I don't know what to do.