HDD not listed in BIOS, but can boot to it if overridden?

Question

I have a custom built Windows 8.1 PC running off an Asus H97I-PLUS motherboard with four drives (2x HDD, 2xSSD) attached with SATA cables. I was fiddling with the overclocking wizard. After a game crashed with lots of graphical glitches I assumed I'd pushed things a bit far and as advised by the wizard, reset the BIOS back to factory settings. In hindsight I may have misinterpreted the statement.

Since then, my computer refuses to boot to the OS, instead giving an error code 0x000000f.

Going into the BIOS, I can see that there is now only one drive to boot from - which isn't the OS drive. I see no options to add a drive to this list.

However, the drives spin up, are detected when I go into the boot override option, the computer boots to Windows perfectly when I select the OS drive and all the drives work perfectly once I'm in Windows.

If I couldn't boot to the drive I'd just be biting the bullet and reinstalling, but this seems like I've just missed an option in the BIOS somewhere. I just can't figure out where!

Can anyone suggest where I might have gone wrong?

Answer 1

Reminds me of a system which I once came across where it would only boot of optical media if it had time to detect what was in the optical drive.

Here's the other thing, just because it receive power and spins up doesn't necessarily mean that all is well with your OS drive. I had the same thing happen to me with some other hardware.

The question for me is how does the OS drive react based on being put into a drive enclosure/dock/another system? How does does it react to be switched SATA port on the mother board? What is the health of the drive like when run under a HDD diagnostic utility such as HDD Sentinel?

If the OS HDD all pass this, then I think a chip on the actual motherboard may be playing up or a setting may be off (unlikely though as this is something very basic. Namely, hardware detection). If this the motherboard is playing up you know as well as I know fixing it is probably not going to be worth it as opposed to purchasing a new one as this involves low level electronics.

If you're desperate to see whether it is now a motherboard fault try applying pressure to relevant chips on the motherboard (overheating can result in parts coming apart. This can negate that depending on how bad it is. Another option is applying heat though this is perhaps what caused the fault in the first place?) and seeing whether the error persists. If it doesn't then you know that your motherboard is coming apart.

Also, have you tried asking the vendor (ASUS) what exactly that code (0x000000f) means? It may give you a massive legup in solving your mystery.

Answer 2

reset the BIOS back to factory settings.

Your motherboard does not have a BIOS. It has UEFI. Confusingly this is often called an UEFI BIOS but it has nothing to do with a BIOS. Both BIOS and UEFI are firmware.

This is important because a PC BIOS usually boots from a bootsector on a disk. EFI on the other hand looks for a boot file on an EFI system partition. EFI also allows signature checking. If the signature does not match it will not boot that file.

What probably happened is that your windows OS was installed in CSM mode (basically UEFI firmware with compatability shims enabled and secure boot turned off), allowing it to boot in the old fashioned way. Now you reset the firmware to default (modern) settings. It now only looks for EFI system partitions.

when I go into the boot override option, the computer boots to Windows perfectly when I select the OS drive and all the drives work perfectly once I'm in Windows.

but this seems like I've just missed an option in the BIOS somewhere. I just can't figure out where! Can anyone suggest where I might have gone wrong?

Use the boot override to boot windows. Check the disk. Is it an MBR partitioned disk or a GPT partitioned disk. If it is MBR then go back to the UEFI firmware and enable CSM.