My pc:

*Asus Z170-P with 6700K cpu

*Corsair 750 RM

*Gtx 1080 Ti Founder Edition

*Monitor Red Eagle IIyama 24' 1080p 144hz plugged by display port cable to GFX.

Few days ago i get power outage. Power outage was because fuse was tripped because of kitchen which was turned on in other room.

When i run pc first time on first boot ( after power outage ) refresh was normal at start 144hz.
When i manually turn off computer and turn on again,and on my second boot it happened. Refresh was lower than 144hz. To make again 144hz i turned off monitor and turn back on again.

So that was bug or that power outage related?

Maybe coincidence and i am worrying for nothing,hehe ?

So conclusion: It happened not just after ( not on pc first power on ) power outage.
But on second time ( second turn ) when i boot to Windows 10.

PS: I tried to reproduce only 3 times by cutting power to pc and powering on and booting again, but 144hz on start. Not able to reproduce.

Maybe coincidence and i am worrying for nothing?