I'm having a problem with a build of mine when enabling XMP. If I enable XMP, the system posts, but when Windows starts loading, the system immediately locks up with the RAM debug LED on the motherboard lit up. Everything is fine if the the I leave it at auto. At this point, I have swapped everything except for the processor and the drive/OS (tested different motherboard but same model). I have no idea what could be causing this strange issue. As a side note, I did just move from an ASUS X570i board that did not exhibit this problem.