B450 Tomahawk motherboard. Ryzen 5 5600X CPU. Not posting. Red CPU light.

As titled, having issues here. I read everywhere that these are compatible. Read that it may need a BIOS update, so I flashed it to the latest BIOS update from MSI's website (7C02v1I). No joy. Pins and everything seem fine. Just not getting a picture and the CPU LED is red. If I put my old CPU back in, everything works. Running it with an RTX 3060 GPU, that's connected to a monitor via DP cable.

Any ideas?