I have a Dell Inspiron 1525 laptop and every now and then it is shut down for no reason with this message on the screen:
internal hard disk drive not found
To resolve this issue, try to reseat the drive.
No bootable devices--strike F1 to retry boot, F2 for setup utility
Press F5 to run onboard diagnostics.
If I just restart the computer it will boot up without problems. This happens about twice a day and it looks like it only happens when the computer has been idle for a few minutes.
I have already tried to reseated the drive, ran the onboard diagnostics and there were no errors.