System Won't Start From Cold Boot

The system in question is the one in my sig.

Whenever I turn my computer on from a cold boot, either

1. The system freezes when in Windows, or
2. I get just a blank screen without even booting the BIOS

I have to do a hard reset by using the reset button, and then everything is normal. Once I'm properly booted I can leave the system on for days without a problem. It happens every time when I completely shut off the computer and try to boot.

Is this a PSU problem?

I would not think that the psu was an issue, have you taken the first step and reset the bios to defaults?

Hi Caddi. And thanks.

No. I haven't reset the BIOS yet, though they are at Defaults at the present moment. I'll try out your advice in the next few days.