There are two kinds of throttling going on. CPU and VRM. CPU is normal - prevents CPU temps going above 100C. The issue is VRMs which have no cooling. And no

There are two kinds of throttling going on. CPU and VRM. CPU is normal - prevents CPU temps going above 100C. The issue is VRMs which have no cooling. And no public sensors. The fix is to add thermal pads to your VRM chips to dissipate the heat to back plate. Entirely solves all throttling issues. Cleaning fans should help too.