Blank Computer screen after reboot

I have a K9N Neo nvida nforce 550 MOBO with a AMD 5200+ dual core and a x1950 pro ati graphics card. I got everything running but at first i got the error unknown processor revision. I fixed this with a forced Bios flash. No i can access my bios and when i start the computer it tells me to hit F1 for setup or F2 to use default settings. If i use default settings it goes to windows and starts up fine. If i go to setup and just his f10 to save and exit the monitor goes blank and nothing happens. The computer is running but the monitor is in standby. If i use the default settings without going into bios the computer works fine as i said, but after i restart the computer i get the same problem and have to reset my cmos everytime i want to get on.