Okay...so I'm sitting at my computer playing Half-Life...I refresh the servers, and bam, the machine appears to go down. Only it was still on...the hd lights were on, etc...you could hear the hum, only the monitor light was flashing like there was no video signal. I had to shut it down by pushing the power button...and when I turned it back on, it wouldn't boot. I could hear the hum...and see the hd lights flashing like it was booting, but the monitor light still flashed like there was no signal. Does anyone have any ideas???