What I did was switch, in BIOS, to AHCI, right after that all it does is show a _ and it's not even blinking. I don't know what's going on or what to do. What do I do? All this from trying to install Windows 7. Edit: Let me rephrase, this computer won't boot. No BIOS, no beep codes, nothing. Just a _. And it doesn't blink. Edit: I took out my RAM and disconnected my hard drives in an attempt to fix it. No dough. Same exact thing. This is very frustrating.