Originally Posted by powerrush777
I am working on a tool that overclocks the cpu, and limits the frequency based on temperature. When certain temperature is reached then the cpu downclocks, it is based on windows power management, and amdmsrtweaker. I want to know how to read cpu amperage in order to calculate the power consumption.
Maybe i can have any help from The Stilt? i don't know how to use the msr registries for reading the cpu power or amperage.
There is nothing I can do unfortunately, as all such information is strictly confidential. Also the power management is solely handled by the SMU, and the documentation for it is only available to AMD engineers. Having an NDA will not gain you a access to these documents either.
The actual power consumption of the CPU can be only aqquired from the SMU. Despite Excavator designs use SVI2 voltage interface, which allows power telemetry the telemetry feature is not used on Excavator. The APM power estimation is not that accurate and it only shows the estimated power consumption of the CPU only. Not very helpful when the total budged is shared between all the domains (CPU, GPU, NB, MEMCTLs, FCH, IO etc).
Also without the knowledge how to program the SMU for desired operation, you have basically zero control on the CPU frequencies. Nothing you can do either from the MSRs or the PCI/-E configuration space (outside accessing the SMU) will change anything.