Good evening,
I have exactly the same problems, which RAMs did you use? I myself have Corsair Vengeance LPX (2x, 8GB, DDR4-2133, DIMM 288) (CMK16GX4M2A2133C13). If you find a solution I would be grateful if you share it here :) Google could not help so far (except for the BIOS update).

Is the RAM you have installed compatible with this mainboard? On which slots do you have the RAM? Just so that this is clarified has also partly related

Have you already bought the mainboard alone or how is this to be understood?

Hello. The CPU is marked. Only in the correct position can work. Any Ryzen motherboard must be Ryzen compatible. The CPU needs heat conductive material but not so much and not so little. Put a nice cooler on it. Too much thermal fluid can isolate the heat. (Ryzen is protected from damage, the mainboard switches off). Of course the cooler must also be mounted well. Possibly without Ram (DDR4) the device does not want to work.

Perhaps it would be better to ask the seller or an expert for help.

This is enough for 6-8 CPU: Arctic MX-4 (4g, 8.50W/m K)