My system is Ryzen 9 3900X on B550M motherboard. When using XMP with 3600Mhz the system does not run stable (although it gives very high performance for the whole system: 92% for CPU, 99% for GPU; 122% for Ram on UserBenchmark). As per advice online, I reduced to 3466Mhz (on Bios) and it runs very smooth and stable and still with high performance -- 110% for RAM on UserBenchmark. When not using XMP the motherboard set the speed of 2600Mhz only. The system run much better with 3466Mhz. Problem was perhaps with the motherboard and AMD system, which cannot support more than 3600Mhz.