Hi, everyone.
I have a GA z170 gaming K3 motherboard currently running an i5 6500 witch I was bclk OC-ing on the old F2c bios. I'm planning to change to an i5 8600k or i3 8350k and I got a custom bios here on the forums thanks to chinobino.
After flashing the modded bios with FPT tool, just to check if it worked I reverted to the F2c, but for some reason it seems the Intel ME firmware won't downgrade.. I tried to remove the battery right after flashing to clear everything but somehow the ME firmware stays the non OC one.
Any ideas what could be the culprit and how to downgrade?

Problem solved thanks to chinobino again! FW was actually downgraded alright, it was the bios settings that were acting up.

how did you maked up?

Here is the thread where chinobino helped me, maybe You find something useful.
[OFFER] Various Gigabyte Z170-HD3-DDR3 BIOSes with Coffee Lake support (5)