Hi all. Working on someone's computer which is really messed up. First, the power button doesn't work on the front of the case. You need to power it on from the back of the case, press the power button on the front, then the reset button to start the boot process. Then, the computer gives one long beep and two short beeps, which I've researched , and it sounds like a video or video card issue. The monitor stays blank so it is impossible to do any troubleshooting that way. I think it is custom-built, so there's no brand or company associated with it. It uses an ASUS M2N-SLI motherboard and it looks like it has two video cards. Any ideas?? I'm lost.