I can't get past the motherboard start-up screen all of a sudden. Help?

There once was a time where I was really good at making things…

Okay. I’m building a PC for my fiancee.

The motherboard: MSI k8n neo4 nforce4
The processor: AMD Athlon 64 3500+
The video card: GeForce 6600 GT
The hard drive: Maxtor something or other.
RAM: Three sticks coming to almost two gigs. I know that doesn’t say much, but it’s almost 1 AM.
Power supply: 500W

All of these parts work, because three weeks ago they made up my PC (minus the power supply, which is new). I know they work because they also were working earlier today (this includes the power supply).

I put the PC together and hooked everything up. I had to install Windows XP new, and three files did not copy over. One was msconfig.I know this is serious. However, the computer was working, everything turned on and loaded up Windows XP okay, and that was fine. The DVD drive works, the hard drive works, but there is no network connection. I suspect that this is because I haven’t installed the motherboard drivers yet.

I downloaded the motherboard’s drivers from MSI, copied them to a CD on my working PC, and then installed them on the PC in question. The install went fine, and it prompted me to reboot. I did.

Now it won’t get past the motherboard splash screen, where it prompts me to press Del for the BIOS. Pressing Del for the BIOS does nothing. The computer will not continue booting past this screen if left alone. There is no power to the DVD-ROM during this – I am unable to eject the disc in the drive or have it take any action.

I unhook the hard drive and power the machine back on. Now I can press Del to get into the BIOS, but there is still no power to the DVD drive. It’s not in the BIOS anywhere. Swapping power cables does nothing to affect this.

I don’t even know where to begin searching on this problem on Google, so I turn to you guys. What the hell did I do, and more importantly, what can I do to undo it and fix things?