Okay, I have an idea. It would be good to know what exactly is causing the problem, but most adapters can be ruled out. Try taking the hard drive out and putting it in another computer with know-good hardware, or if you are a boss, an external adapter. A PSU is your power supply. That big thing with a bunch of wires coming out that you plug a 3 prong cord into from the back.
And for this Linux discussion... Windows XP all day everyday.
I'm far from an expert.