Z97-A BIOS Boot Priority list

Hello everyone,

Recently I have found some strange behavior in the BIOS Boot Priority list of my Asus Z97-A motherboard in EZ Setup mode.

It shows a boot device named "ubuntu".

UEFI mode is disabled. Only Legacy mode and CSM boot is enabled for all devices.

At first I thought it was left on one of the hard drives. I have only two NVME M.2 Samsung SSDs in my PC. No SATA drives.

So I removed both SSDs from the motherboard. Then I disconnected all USB devices. Then I reset CMOS with jumper, loaded default BIOS settings. Flashed BIOS with latest firmware. Reset it a few more times.

But I still have unknown boot device "ubuntu" in EZ mode only list. Literally everything has been physically disconnected from the motherboard and reset numerous times and it's still there. What a ...?

 

I don't use the M.2 slot on the motherboard because it only supports x2 mode.
Instead, I use two Asus Hyper M.2 x4 Mini Card PCI-Express adapters.



I just can't figure it out...
Where did it see the 'ubuntu' boot device when all SSD's are disconnected from the motherboard ?!

I tried changing 'Fast Boot' settings to On / Off and UEFI / Legacy modes, but to no avail.

EZ Setup mode always lists this 'ubuntu' in Boot Priority. When all SSD drives are disconnected from the motherboard and only this 'ubuntu' is listed, the system goes through POST screen and then returns to BIOS EZ mode.