Windows 10 Automatic Repair - switching between UEFI and non UEFI devi

Hello. So i got automatic repair after changing boot order from UEFI USB KINGSTON to P1 Samsung SSD 840 EVO. I am able to get through to Windows 10 but after restart after automatic repair. So i am needing 2 boots now.

Screen:


And my question is this related to my switch between UEFI and NON UEFI device or that doesnt matter?

My motherboard is Asus Sabertooth Z97 Mark 2.

System was working fine few days on P1:Samsung SSD ( MBR ). Problem appear when someday i just change again ( maybe my 5 switch ? ) boot order from UEFI USB KINGSTON to P1:Samsung SSD ( MBR ). So is this related to this or that doesnt matter?

System is installed and formatted on MBR partition. So i guess its on LEGACY MODE. So i dont have boot manager SSD Samsung 250 EVO in UEFI. Only have P1: SSD Samsung Evo 250 GB like on screen.



Problem started after memtest86 session bootable from USB .After finished memtest86 test i change in my UEFI boot priority from :"UEFI USB KINGSTON" to "P1 SSD SAMSUNG EVO 250 GB ( MBR partition )". .And then everytime i restarting Windows 10 by button RESTART from START in next boot i have Automatic Repair. On next boot i am able to boot fine to Windows 10. It's a bit weird that it reboots twice and then get's through..

Maybe something with UEFI and boot of my SSD which is MBR? Or that doesnt matter?

But from what i know UEFI can also boot from a MBR disk.

And it happened just after my finished memtest86 session. So its only coincidence that happened after memtest86 session or not? Thx

So i am after format this time with GPT partition and no problems . But i want only know what caused that Automatic Repair before format. Software , bios uefi or hardware? ( that happened after memtest86 session ).

So i ask somebody about reason of Automatic Repair.
And he said :"You need UEFI to boot from a GPT drive. But UEFI can also boot from a MBR disk. So this in itself shouldn't make Windows think that it needs to repair itself."


So propably switching from UEFI device ( UEFI USB KINGSTON ) to non UEFI device ( P1:Samsung Evo 250 GB ) was not issue ?

Ah and last thing. During that period with Automatic repair i get second issue too. And i dont know if it was related to Automatic Repair or not.

Task manager and event viewer was not responding and some of the applications stop responding. I was clicking and nothing happening. Next. Next when i was clicking 3dmark 11 TEST i was getting weird system slowdown. Almost all programs stop working. Start menu was not responding. All applications wont responding and became very laggish. Gets stuck on "Logging Off" when attempt to shutdown or restart. System become unresponsible and laggish. I cant do almost everything. I cant restart system because START button stop working.
Opening some file taking 10 second. I must force hard reset to work properly again system. Almost everytime
when i click run test in 3dmark 11 causing this issue.


So that was related to that Automatic Repair or not?