I have a home built system and it is 1.5 years old. About 6 months ago it started to get really fussy about finding a boot drive on startup. Sometimes the boot would stop at the Mobo initial splash screen and sometimes it would continue but give me a "unable to find boot device" error. I can get it to work after one restart and after switching my HDD sata and cd-rom sata cables to new slots on the Mobo. But recently this problems occurs almost on every boot up. Any ideas? Thanks.
(And yes I have updated anti-virus program but no hits)
You may have a sata or ide port going bad. Set your sata bios setting to IDE, or check it in case it's changed. I once left an old non-boot floppy diskette in the floppy drive and forgot about it. Had to remove it.