wierd monitor problem, what can it be.

Okay i posted this question in graphic card area but no luck . i thought maybe this would be a better spot.Okay, my computer does a wierd thing. WHen we're done using the computer we always unplug the computer, (not the monitor) to keep any chances of power surges. when we leave it unpluged for a few minutes or go to turn it on later, the computer comes on, but the screen has all these line and colors and like when you try to put a old nintendo game in the 8 bit nintendo system and the pictures comes up all wierd looking with wierd shapes and stuff. you can't see anything. Now when i turn it off and turn it right back on it does the same thing, and no matter how many times I turn it off and back on it keeps doing it. now the wierd thing is that to fix it I have to turn off the computer; but then unscrew the monitor video card hooked to the back of the computer on the video card and screw it back on. Then when i restart the computer it works fine the window screen comes up and it's like nothing happened. Why would i have to unscrew the video cord to make it work again. I don't have any issues with it, when i play games or anything video wise just when i unplug the computer. I don't think it does it when i turn the computer off and leave it off, not unplugging it, just when i unplug it. THe video card seems to work fine. It'a a radeon 7500 card.the case stays cool. I have two case fans blowing in the case . One blowing on the cpu and one on the video card. I just went on the website to look around and i noticed the driver i downloaded is the newest one. Do you think that could be the problem. I didn't have this problem with the driver Cd that came with it. I check the website and found the catalyst driver that goes with it. It was the very first one they had. Hey do you know of a program you can download that will tell you the temps of your video card. I have a program that came with my motherboard called easy tunes 4, it tells me the temps of my cpu but not video card. It's not overclocked. My temps of my cpu run great. Right now the temp of my Cpu are 27 deg. celcius. I'm going to install the old drivers and see if that fixes the problem . ANymore ideas would be usefull. THanks.

THe only thing i can think of is that after i installed the ati catalyst driver it started doing it. I decided to uninstall the catalyst driver, and installed the normal driver to see if it there was a issue with the catalyst driver but it still did it. THe monitor is a 2001 or 2002 17 inch hp monitor. It don't have any other issues with it at anytime just when i unplug it.okay, I downloaded the old drivers and installed them back in, but it didn't solve the problem. It's wierd that when i just turn the computer off, it doesn't do it, only when i unplug it. I can leave the computer off all day, then turn back on and will work fine. It's only when i unplug it does it do it. Whats going on here?

The monitor works fine. Any thought or ideas will help. Thanks.

My hardware, if that helps is:

Athlon 64 3000
thermaltake 480 watt
radeon 7500
socket 754 gigabyte GA-K8NS K8 triton motherboard
and 512mb memory