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CPU Package / CPU Core Power
#1
Hello

I've been looking for an answer for this and i can't find it, if it's a common question - sorry for that.

Under full load my cpu is rated as 95W -  amd ryzen 1800x has:
CPU Package Power (SMU) 100-110W - ok, this is power consumed by CPU
CPU Core Power (SVI2 TFN) 190-200W - but what is that?, can someone explain to me exactly what this value represents?

and

SoC Power (SVI2 TFN) 10-12W - also what exactly this represents?

Would appreciate Your help.
Thank You

Pawel
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#2
AMD Zen CPUs have multiple voltage rails: VDDCR_CPU and VDDCR_SOC
CPU Core Power (SVI2 TFN) is measured via SVI2 telemetry and it reflects only the core (VDDCR_CPU) rail. SoC Power reflects the VDDCR_SOC rail. So VDDCR_CPU + VDDCR_SOC + (additional rest-of-chip power that can't be measured) should equal the total CPU Package Power.
The fact that CPU Core Power (SVI2 TFN) reported is so high (even higher than CPU Package Power) means, there's some glitch in the measurement. It's most probably an occasional invalid measurement during a transient state.
I suggest to watch the CPU Package Power (SMU) value only as this is the total telemetry provided internally by the CPU.
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#3
(01-04-2019, 09:16 AM)Martin Wrote: AMD Zen CPUs have multiple voltage rails: VDDCR_CPU and VDDCR_SOC
CPU Core Power (SVI2 TFN) is measured via SVI2 telemetry and it reflects only the core (VDDCR_CPU) rail. SoC Power reflects the VDDCR_SOC rail. So VDDCR_CPU + VDDCR_SOC + (additional rest-of-chip power that can't be measured) should equal the total CPU Package Power.
The fact that CPU Core Power (SVI2 TFN) reported is so high (even higher than CPU Package Power) means, there's some glitch in the measurement. It's most probably an occasional invalid measurement during a transient state.
I suggest to watch the CPU Package Power (SMU) value only as this is the total telemetry provided internally by the CPU.

Thank You very much for explaining.
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#4
(01-04-2019, 09:16 AM)Martin Wrote: AMD Zen CPUs have multiple voltage rails: VDDCR_CPU and VDDCR_SOC
CPU Core Power (SVI2 TFN) is measured via SVI2 telemetry and it reflects only the core (VDDCR_CPU) rail. SoC Power reflects the VDDCR_SOC rail. So VDDCR_CPU + VDDCR_SOC + (additional rest-of-chip power that can't be measured) should equal the total CPU Package Power.
The fact that CPU Core Power (SVI2 TFN) reported is so high (even higher than CPU Package Power) means, there's some glitch in the measurement. It's most probably an occasional invalid measurement during a transient state.
I suggest to watch the CPU Package Power (SMU) value only as this is the total telemetry provided internally by the CPU.

Hi Martin 

Wonder know which interface or MSR which can be use to get the package Power SMU data. Thank you so much.
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#5
This should be documented in the public Processor Programming Reference (PPR) for AMD Family 17h document.
If it's not there, then this information isn't public and cannot be disclosed further.
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