My grandmothers computer moniter is a 20 inch Soyo LCD moniter, its a little over a year old, and recently she has been having problems with it. When she uses her computer, the moniter stays on for about 15 minutes or so, and then shuts off. She doesn't know whats wrong with it, I haven't had the chance to see it myself yet. Any suggestions?

If you let the “Power Save” mode take over, the screen turns off and goes into standby.

I am guessing your grandma is not very techy!
I am guessing that is the issue.

Your computer doesn't go into standby while your using it. That's the problem. Like I said though, I haven't had a chance to look at it myself.

Ask her what she means by 'shuts off.' Does she mean the screen goes black and the power indicator light stays on? Does she mean the screen becomes unresponsive? Does she have to press the power button to get it back on again?

Heat problems?