Comp won't boot

Okay; here it is. My son's computer suddenly won't boot-up. Here's what happened. Last night, he's playing a game, he finishes, then he shuts down the computer in the normal manner. This morning, he goes to turn the computer back on, and it won't boot-up. So here I am, "Don't worry son, I'll fix it for you." Several hours later, I'm wanting to throw the damned thing out the window.

What we're dealing with: Toshiba computer, 300mhz PII processor, 64mb sdram, Windows ME.

Symptoms: I push the power button, it comes on, I hear the fan, but that's it. No other noise, no beep, and the monitor stays black. No error message…Nothing. There is power to the CD Rom.

Actions taken so far: I checked to make sure the power cord is plugged in all the way, made sure the monitor is securely connected, I even changed the power cord to see if that had anything to do with it. I opened the tower, and checked all of the ribbon cables, and all of the power connections. That's all good. I then tried disconnecting everything but the hard drive, but it still doesn't boot-up. HELP!! I greatly appreciate any advice anyone can offer. Thank you.

--Sam