power consumption : Tytanick, settings below 900mV seem not to work on RX570/580 cards I have here (Sapphire Nitro, Pulse). Didn't try any else.
With SMOS, the lowest consumption I can achieve is ~150W at wall. Asus Prime H270-Plus with January2018 BIOS, CPU G4560, 4GB RAM, single RX580 Sapphire Nitro at this moment but I tested with different cards up to 7 installed, 240V Europe, Corsair TX-850M (should be about 89.5% effective at this load). GPU 1000MHz, VMEM 1900MHz, underclocked BIOS.
MB+CPU+RAM consume 35W idle in Windows and SMOS without any GPU installed - 35W measured at wall [!] after power supply ineffectivity etc. With single GPU installed but not mining, Windows consumes about 47W ; SMOS 65W. Windows configured with High Performance profile, no CPU savings, no PCI-e savings in BIOS.
GPU Voltage set in web interface | Consumption at wall with SMOS
1100mV 180W
1000mV 170W
900mV 153W
850mV 153W
800mV 153W
750mV 153W
I feel it does NOT work as it should.
Powerstage 0 153W
Powerstage 1 153W
Powerstage 2 153W
Powerstage 3 153W
Powerstage 4 153W
Powerstage 5 153W
Powerstage 6 153W
Powerstage setting has absolutely no effect on power consumption at all. All these tests conducted with 1000MHz GPU, 1900MHz VMEM, 27.2MH/s. This particular card maxes out at 1950MHz memories no matter what voltage I apply, it's a crap.
I know PowerStage settings work in different settings and scenarios - I'm running some rigs with 1100MHz GPUs, 2000+MHz VMEMs and there is big difference in power consumption between PS6 and PS2. Generally I'm using PowerStage2 almost everywhere because PS1 and PS0 do NOT bring any decrease in real consumption / temperatures and everything above PS2 is heavily increasing power consumption. Because I'm totally stable at PS2, that's what I use ; difference in power consumption between PS6 and PS2 is about 400 Watts with each [!] rig I have.
Here, in this particular case, PowerStage has totally no influence on power consumption.
GPU voltage settings BELOW 900mV DO NOT have any effect on total consumption in SMOS, while they work in Windows. Decreasing GPU and VMEM in ATI WattMan (newest drivers, Adrenaline v18.2.3 dated 22/Febr/2018) below 900mV works correctly in Windows, HWINFO64 and GPU-Z report lower voltages for both memory and GPU and it is reflected on real wattage measured at wall. I can get to 750mV GPU and VMEM with 120W total rig consumption at wall and yes, it's stable at 1000/1900MHz.
Lowest I'm able to achieve with SMOS is 152-153W. I've tried so much...
So, the effective delta in power consumption between Windows and SMOS can be 20 Watts per card. With 10 card rig, that is 200 Watts which really is a lot, especially if you have 10+ rigs. Will you please look into this ? Any diagnostic output you need ? I can give you SSH access if needed.
And it's not just about power consumption - it's about temperatures, too. Of course Windows10 runs these cards cooler, because it is able to use lower voltage.
I even tried to lower voltages in BIOS, programming 850 (manual) or 65282 even 65281 in appropriate frequencies. Makes no difference in both Windows and SMOS.
Measurements in Windows taken with lowest voltage set as 65282 in BIOS. I'm not saying this is equivalent of 750mV, I'm saying power management in Ubuntu might be "not optimal" and potentially not working below 900mV. Regardless of what is in BIOS, it works in Windows.
Any hints or tips, please throw my way. Is there anything in Ubuntu like HWINFO64 in Windows ? How can I display parameters of AMD RX570/580, such as frequencies, voltages etc ?
right undervolt does not work, I'm doing 850mv 1150 core, the house is getting high electricity from the wall, it was not like this before