Windows Boot Manager is mandatory?

[plzhelpme1]

I'm sorry if this is a sore topic or easily found information. But, I searched and didn't find an answer, so I'm here. I have recently built a PC, specs on my profile, and out of no where started getting this boot error telling me to connect an appropriate device and restart. After messing around a little bit, I found out that the cause of the issue is at some point WBM had been been replaced by the actual SSD for priority boot. I resumed WMB to #1 and my PC boots without a hitch. My question is why?

 

[helpstar]

Did you install the ssd after the windows installation?

Did you fresh install windows or do you use an old installation from another system?

for some reason, the boot drive could be defective or not recognized correctly while booting. SATA data/power cables could be defective of the boot drive, bios could be resetted because of empty Bios battery....

conclusion:
it´s not normal, that your boot priority changed out of nowhere

What does WBM mean in boot priority list? Why isn´t it installed to the SSD?

 

[plzhelpme1]

My OS is installed on the M.2 SSD, so there's no sata involved. It's a fresh install of an OS on a brand new drive. WBM = Windows Boot Manager. It's the only option that works to boot the PC.

 

[helpstar]

What´s written behind WBM?

Did you install Windows in UEFI mode?

the 500GB Samsung SSD 850 EVO isn´t installed yet?

Before you installed the OS, the default boot device was?

 

[plzhelpme1]

What´s written behind WBM?

Did you install Windows in UEFI mode?

the 500GB Samsung SSD 850 EVO isn´t installed yet?

Before you installed the OS, the default boot device was?

Written behind? I don't understand.

UEFI mode? It was just a normal install through USB.

The 500GB was installed after the OS was installed on the M.2 SSD.

Before I installed the OS, the M.2 was set as priority 1 for boot.

 

[helpstar]

I thought something like this:
http://www.eightforums.com/attachments/tutorials/23181d1371586657-downgrade-windows-8-windows-7-a-windows-8-downgrade-006-sb-posting.png

But that´s not necessary to know anymore.

"The 500GB was installed after the OS was installed on the M.2 SSD"
That´s it. When you installed the other drive, the BIOS organized the boot priority new.

 

[plzhelpme1]

When you installed the other drive, the BIOS organized the boot priority new.

Hmm, so it's just something new that I have to give boot priority to? Wonder what happens when I need to reinstall.

 

[helpstar]

If you reinstall, the boot priority should stay the same, because the hardware doesn't change. If you plug the ssd into another slot, it could be rearranged by bios, but that's dependent on how the programmer implemented this situation.