my motherboard crashed oneday. later that night, i kept hitting the power button for a couple of minutes and it started working again. Now when ever I start my laptop, the american megatrends screen pops up and i have to hit F1 to continue and my compter clock and date gets reset everytime i start my computer.
Sometimes the BIOS gets corrupted, and in an effort to fix this, the BIOS will default all the settings. If you switch the settings back, and then Save and Exit, and this still happens, then the battery needs to be replaced, or the pins to short the CMOS on the motherboard are shorting for some reason.