Question PC only boots on Windows Boot Manager (Win10)

[Arrrtyom]

When I started the PC today, it gave an error message about "boot media not found, insert boot media etcetc".

After some fiddling about I found that I had to list Windows Boot Manager (Disk name) as my first boot priority for it work. Previously the boot priority was #1: (Disk Name), #2: Windows Boot Manager (Disk Name) and it had been working fine for months. I found this thread, and okay, booting from the boot manager seems normal. But if booting from the disk was working for months, why did it randomly decide not to boot today? Should I be worried about something? I'm pretty confused now.

The disk is a 240GB SSD Liteon PH5-CE240 if that's relevant! It's also in slot P2 (if they're called slots) while my other HDD is in P0.

 

[Colif]

Can you show us a screenshot of disk management?
right click start, choose disk management
take screenshot that shows both drives and the list of partitions at top with full descriptions
upload to an image sharing web site and show a link here

If WBM is the boot item of choice, it makes me think the Boot drive is formatted as GPT. the order of drives on a GPT system doesn't really matter and its possible the system has been skipping drive 1 up until now and using wbm anyway, though it is odd strange it just changed its mind now.

WBM stores a list of drives that have the boot info for installed drives, it can work with GPT or MBR drives.

What motherboard is it? could be you need to replace cmos battery as its one reason the boot order might have changed or something.

 

[Arrrtyom]

Can you show us a screenshot of disk management?
right click start, choose disk management
take screenshot that shows both drives and the list of partitions at top with full descriptions
upload to an image sharing web site and show a link here

If WBM is the boot item of choice, it makes me think the Boot drive is formatted as GPT. the order of drives on a GPT system doesn't really matter and its possible the system has been skipping drive 1 up until now and using wbm anyway, though it is odd strange it just changed its mind now.

WBM stores a list of drives that have the boot info for installed drives, it can work with GPT or MBR drives.

What motherboard is it? could be you need to replace cmos battery as its one reason the boot order might have changed or something.

Motherboard's a Gigabyte B250M-D3H