HP Omen, new GPU doesn't work.

[sew3663]

I bought this PC when GPU prices were crazy.  I pulled the 3060ti from the HP and  put it into my main desktop.  I'm now trying to get around to selling this one as a working PC.  It contains all of the original components except I put in my old GTX 1050 (2GB) and bought some silicon power 3200 speed RAM (2x8GB).  The RAM and GPU both work on my other PC (with an ASUS Z590P Prime).

I can't get a signal from the computer at all.  Since these motherboards lack features, the GPU is the only way I can test the signal.  I can't reach BIOS or anything.  The computer POSTs, so there is that (I had a 10th gen CPU I put in here which wouldn't even POST). I could look for a new BIOS, but if I can't even get into the BIOS, how am I supposed to get it updated?

What I have tried:

I have tried both the HDMI and DP. 

The GPU fan spins.

I have reseated the GPU

[sew3663]

Just tried a couple of other things:

I pulled the GTX 1050, confirmed it worked on another PC. 

I put the original RAM and GPU in the HP, and nothing.

I also cleared CMOS, at least I think I did.  I unplugged the power, pulled the mobo battery, and noticed a CMOS jumper that I removed and placed on the other two pins (there are three CMOS pins).

Still nothing.  I get power, the CPU and GPU fans spin and the RAM RGB stays on.  But no signal.  Last time I tested this PC was only a couple of months ago and it worked fine.