Trouble with my Dell optiplex GX150 deskstop
 

Hi, I have got a dell gx150 desktop with P3 processor and Bios ver A11. when i start it up it goes through the DELL boot screen, and I can still get the prompt to press F2 and/or F12. After this, this reboots itself and starts again till it gets to pompt screen before it reboots again....