TLDR: MSI doesn't play well with pci gen4
cpu:5950x
ram:16GB crucial ballistix
gpu: rx6900xt
psu: evga 850w
My father recently rebuilt his pc using a MSI X570 UNIFY and after updating the bios to recognize his cpu we were still having issues. We called up MSI support and they couldn't figure it out. I finally took a shot at it myself and found out it was running well with my old reliable 750ti in it. Now that I could get into the bios I found the pci setting and changed them from auto to gen3. Save and restart. Shutdown after windows booted. installed the new gpu and it works now.
Putting story up here hoping it helps someone from the same headache my father went through.