How to reduce core voltage when targeting a Linux distro as my OS

[Toxicable]

Hey guys,

So im trying to reduce my power usage since im very close to the limit after doing BIOS flashing but I havn't been able to figure out how to do this when targetting a Linux distro as my OS

My GPU's are Nitro+ 570's

I've tried using SRBPolaris and setting the voltage in there but after applying the bios I noticed that my voltage did not change
I've also tried using the Claymores argument that sets the core voltage but this also had not noticeable effect on Wattage usage or in monitoring software

[Subw]

You can't.

[hopfi2k]

You can't.

As you can do it for the RX470/480 by patching the 'polaris10_smc.c' drivers (works perfectly fine for my rig), it should work with the RX570/580 too.
Unfortunately I don't have a RX570/580 and therefor can't test.

Cheers
Andy

[cvsea]

I gave you a hint in the other thread. Did you look it up?
Anyway, I asked somebody to send me a vbios from a 570 but didn't get it.
If you would send me a copy I can look to see if the same fix can apply.

[Toxicable]

I gave you a hint in the other thread. Did you look it up?
Anyway, I asked somebody to send me a vbios from a 570 but didn't get it.
If you would send me a copy I can look to see if the same fix can apply.

Yeah I gave it a shot but im not overly good at that kind of thing, I just PM'd you a link to the BIOS

[cvsea]

Got it. Sent you a reply.

[cvsea]

So it looks like I was able to modify VoltageObjectInfo and insert VDDC offset register. Try it and see if it's stable. May need a different offset depending on chip quality.

[Elange]

You can't.

As you can do it for the RX470/480 by patching the 'polaris10_smc.c' drivers (works perfectly fine for my rig), it should work with the RX570/580 too.
Unfortunately I don't have a RX570/580 and therefor can't test.

Cheers
Andy

Hi. I did the polaris_10_smc.c patch and it's working perfectly. However, on some rigs 818mv works for 4 cards and not working for the other 2. So, I have to raise it to 850mv for all cards in rig, which is really a waste.

Has anyone found a way to downvolt GPUs individually? Looks like the hwmgr structure that's being passed to the polaris_get_dependency_volt_by_clk function contains card index information, so we can use an array instead of a fixed value, but I'm not really that much of a programmer to dig that deep. I am also a bit scared to do modifications and try them in a rig worth $1500. ))

BTW, it's funny, this hack is dated 2016, yet the latest amdgpu driver (I have 17.40) still does not process core voltages the way Windows does. I wonder why the AMD software engineers never fixed it.