Still sounds like pcie isn't seated all the way. Or more strangely, it might be in the wrong slot. Intel can be fiddly. On the motherboard, there's only one, ignore this.
Its possible that you might be able to test the card in a lower 1x or 4x slot but the back end of the slot would need to be open ended.... tnot possible on your board.
Now, you shouldn't need to uninstall windows and start over. Actually, You can just plug into the igpu and try to restart the system as is.
If you're not getting past basic post, there's no power on beep from the MB, and you're plugged into the igpu, then you should regain control of the bios without having to clear cmos.
I did this all the time on older i5 machines from Dell and similar. The Intel igpu will turn back on when there's no pcie GPU detected, no need to clear cmos to get it back, even if you disabled it before you shutdown to install or after you installed and booted.
Otherwise you're saying its hanging on post. Regain control, use the igpu if possible and disable fast boot and quiet post.
Lots of edits*
