Monitor shut downpalooza

Ok, here's the problem, my computer is using two hard drives, one SATA and one ATA, I regularly swap my ATA to another computer at my friends house cause he hasnt recieved a hard drive for his new computer and we like to lan it up at his house. This has not caused any problems up to this point. Last night upon returning home and reconecting the ATA drive to my computer I began having problems when Windows XP pro loaded up. Everything runs smoothly until it gets to the windows logo screen with the loading bar where the screen flickers a little bit and then is turned off by my computer. My monitor isnt losing power, it just shuts down like I had turned off my computer even though the rest of my components in my computer remain on and I can hear the normal start up noises from all parts. I have no clue what to do about this problem and Ive spent a lot of timing futzing around, the thing is I havent touched any of the display settings at all. Thanks in advance for the help.

that makes a lot of sense and i feel really foolish for not thinking of that, windows is showing up now. Thanks for the help.