Intel | Desktop Board 01 21 B6 E1 E2 Er New

Look for a white label on the motherboard with a format like:

Based on this specific sequence ( 01 -> 21 -> b6 -> e1 -> e2 -> er -> new ), here is what you should check first. intel desktop board 01 21 b6 e1 e2 er new

Because this error is often a race condition (the board resets before the voltage regulators stabilize), try this brute force method: Look for a white label on the motherboard