It seems like this motherboard is too old, just got the reply back from GigaByte. Short, but to the point
Answer:
Hello,
Sorry but this board doesn't support boot from the PCIE SSD.
9/8/2020 1:37 PM
Also got this on a follow up question:
Question: Thanks for the quick reply.
I guess the BIOS does not have full UEFI compliance?
Is there any GigaByte motherboard for Intel socket 1155 LGA that supports boot, since I would like to keep the processor? 9/8/2020 3:33 PM
Answer:
Hello,
We have check the Intel Z68 and Z77 Chipset motherboard doesn't support boot from PCIE SSD.
Intel Z87 and Z97 motherboard support it but the CPU socket is 1150.
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So I guess Z87 or Z97 if I want to keep my i7 2600K