Ryzen 5700x doesn't boot on B350 Gaming Pro Carbon

I flashed the BIOS, reset the CMOS battery, RMAd the new CPU, but nothing. Powers on (case light comes on blue instead of the normal white) all fans spin, but no display.

I've reinstalled my old 1800X and the PC is working perfectly, so I don't think any parts are bad.

Is there anything else I can do other than a new motherboard?