I have a custom made AMD Athlon 2.0 gigahertz PC with Windows XP Pro SP 2. I have an ATI Radeon 9200 graphics card installed. I just installed a new CPU fan after finding out the other one wasn't working. Before that, I was trying to reinstall Windows XP. My problem is that, when I turn on my computer, the screen is completely blank, no BIOS or anything. Also, the computer won't turn off by just pushing the power button. I have to either hold on it or unplug it. All the fans work except one small fan that seems to be connected directly to the motherboard. All the lights turn on. I can't figure it out.