Monitor Troubles

I really dropped the ball on this one. I was messing around and, accidently set my screen resolution to 1600×1200. I should have known my montior would not support this but being me, I applied the new settings. Now I can’t make out anything on my monitor at all. Is there anyway to set my resolution back to 800×600 without using the screen or am I screwed. Any help is greatly appreciated. Thanks.