I can't get my Dell Optiplex 755 to boot up from HD or CD drives. I don't get any start up screens either. When I hit F12 to change the boot sequence, I just get beeps, but make no real progress. Could the Master Boot Record be corrupted? This system has 2GB or ram and 250 GB HD.
Any help would be appreciate.
A broken MBR would display a message saying that no bootable device was found.
Are you sure your bios has F12 for boot menu, some bios use different keys, you could also go into bios and make changes there.
Also old PCs with MBR bios will not boot UEFI disks.
If you get no output on screen at all you should try using a different output, if you have a CPU with integrated and a discreet GPU try both.
You should always get at least some output on screen so that's what you should fix first.