AMD Navi card power monitoring

[Jurrunio]

First of all, thank you for releasing such a useful tool. It helped me so much in tuning hardware with all this data.

So recently I've got myself into an argument of whether AMD has graphics card power draw monitoring (to the level of Nvidia's implementation) yet. I'm told that Navi does because the ASIC power reading is close enough to what a wall power meter reads (minus the rest of the system's estimated power draw of course) according to his testing. I am not so convinced though, partially because past Radeon cards only monitored power rails for the GPU core and memory, mostly because it's exceeding the power limit value programmed into its BIOS. I also noticed that ASIC power reading is only giving whole numbers, unlike the core and memory power figures (though it could just be an accuracy issue).

To sum up, does Navi cards have accurate power monitoring for the entire card? If it doesn't, then how is the ASIC power reading generated?

 

[Martin]

This can be probably answered by AMD only as they know exactly what the number reported exactly means. I believe that the GPU chip power and a few other rails are quite accurate as this telemetry comes from the current measurement at the VRM/SVI2. But other rails (and this is not just the case of AMD, but all other vendors) cannot be measured as they lack such feature so their power is usually estimated using modelling based on activity counters or constant (RoC). But only AMD engineers know how accurate these numbers are. Anyway, I believe they have no reason to lie here or hide something, but try to provide the best possible numbers because the GPU's power management relies on this too.
Another thing are board vendors where things like the recent "Power Reporting Deviation" come into play, so theoretically they can skew these values. This "deviation" is being reported for CPUs, but voltage regulation in GPUs is similar (SVI2-based).