Sony Trinitron Monitor on the Fritz?? need help :)

Hello. As the title states, my 20" Sony GDM-2000TC Trinitron monitor is on the fritz. Here is the problem:

It inexplicably gets a green or red tint all over and sometimes "BCF" flashes in the top right corner. When the BCF is flashing, it seems like the screen is trying to fix itself. Sometimes in can and other times in just flickers occasionally to a different shade. The manual says to reset the CLAMP when this happens. I've tried many times to go into the menu under USER CONFIG and "reset the CLAMP" (it has two options, AUTO and SYNC ON G - I don't know what either means). Some I'm kind of lost here. There is also another setting..."BCF" and the options are "AUTO" or "MANUAL".

Anyway, sometimes the monitor works fine and other times, the color is all messed up. Also, sometimes when I go into a game (lately BF 1942) and the screen was fine, when the screen clicks over to the game it instantly gets the green tinge. Could it be my video card? When the monitor is working fine it looks great....Any ideas>?

I'm hoping to not have to buy a new monitor...this one looks great when it's working.

thanks