Originally Posted by mynm
I have one question about your 590 nitro+, do you see a 1.181v for the dmp 3 and 1.15v foe dpm 7. It seems that 580s and 590s with hight clocks are having this problem.
Yes, at stock it was exactly like that. For some reason, 62282..62288 pointers don't point to a true dpm voltage, my opinion on this is that Sapphire uses an auto voltage calculation method based on asic quality.
As I know there are 3 ways to set the dpm7 voltage on Polaris:
Manual voltage mode (aka software set) - uses voltage under 62282..62288 or manual voltage if specified.
Auto voltage when 0x10A byte in the ASIC_ProfilingInfo is set to 01. Voltage is being calculated depending on the ASIC quality, the voltage also depends on gpu temperature under load. (my card has this voltage "mode" by default).
Auto voltage when 0x10A byte in the ASIC_ProfilingInfo is set to 00. Voltage is set by bytes 0x102 and 0x103 in the ASIC_ProfilingInfo (usual stuff, i.e. 101875*4=407500 -> 4075 = FEB in hex -> EB 0F set in bytes 0x102 and 0x103) I think my old HIS RX 480 used this voltage mode with properly set voltages under the 62282..62288 (dpm3->dpm7) pointers, cannot check this anymore tho as I've lost the original bios for this card.
Extra (buggy?) voltage mode:
Auto voltage when 0x10A byte in the ASIC_ProfilingInfo is set to 01. However, the voltage is not being calculated depending on the ASIC quality and under load is set by bytes 0x102 and 0x103.
My friends 590 SE had that by default. I have a theory of why this happens - some gpu dies are not properly tested/binned when manufactured and the algorithm which chooses the voltage depending on the ASIC quality does not work. It's a bit strange because of GPU-z shows ASIC quality as normal.