There are no motherboard settings pertaining to thermal/power limits as there are on most Intel motherboards but we will test the 6700 on a different board in the near future to see if we can shed some light as to what exactly is responsible.
APM. You can disable it using amdmsrtweaker
. In my case (MSI FM2 ITX board) disabling turbo in the BIOS also disables APM.
BIOS and Kernel Developer’s Guide (BKDG) for AMD Family 15h Models 10h-1Fh Processors wrote:
Application Power Management (APM) allows the processor to deterministically provide maximum performance while remaining within the specified power delivery and removal envelope. APM dynamically monitors processor activity and generates an approximation of power consumption. If power consumption exceeds a defined power limit, a P-state limit is applied by APM hardware to reduce power consumption. APM ensures that average power consumption over a thermally significant time period remains at or below the defined power limit. This allows P-states to be defined with higher frequencies and voltages than could be used without APM. These P-states are referred to as boosted P-states.