failed boot Failed PC boot that triggers BIOs reset

[HMBCP]

hello everyone :) I recently upgraded my pcs mobo and cpu to an i7 9700k and a rog strix z390-f gaming mobo (I took these parts from my partners Scan 3XS system so they have been professionally overclocked) but i have been finding im having booting problems after a BIOs update. This only happens maybe every other day but its enough for me to be concerned. When i boot my pc, the screen will not turn on and remain black and i get a green light next to boot on my mobo. The only way i can get my pc to boot is to unplug my index from my GPU and restart. The problem with this is each time this happens, bios will reset and doesnt detect windows so i have to go into bios and reset up my pc to be able to boot windows. 

I feel like there can be a few culprits to my problem. The first thing i think it may be is having my index plugged in on boot, but this has never been a problem before and id rather avoid unplugging my headset from my gpu each boot as not to damage the display port. Secondly, could this be a problem caused by a dying cmos battery? Im not too sure on this since the time does not reset after turning my pc off. Thirdly, could this be a problem with my boot drive? and lastly, is this caused by a bad BIOs update? 
I'm not sure what to do next to fix this problem, but any suggestions are appreciated. 

[emosun]

Did you change the motherboard and not reinstall windows

[HMBCP]

5 minutes ago, emosun said:

Did you change the motherboard and not reinstall windows

yep, since i was keeping my drives i just switched out the mobo and cpu and left my windows install as it was 

[emosun]

22 minutes ago, HMBCP said:

yep, since i was keeping my drives i just switched out the mobo and cpu and left my windows install as it was 

Ok well its common pratice to do a reinstall as various issues occur when you just move an installtion around random hardware. SOMTIMES windows works fine after a board change but it has no real reason to work fine.

[HMBCP]

3 minutes ago, emosun said:

Ok well its common pratice to do a reinstall as various issues occur when you just move an installtion around random hardware. SOMTIMES windows works fine after a board change but it has no real reason to work fine.

will try this, i want to upgrade my boot drive anyway (230gb is getting a bit snug) so may as well do this alongside a fresh install of windows. thanks for your help!