Update reduces Color Accuracy in favor of Power Efficiency | AMD GPU|

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Hello.

After a recent update, not sure which one exactly, the contrast of the screen gets reduced on the lower consumption power profile settings… I think. I don’t actually know if it’s contrast that’s being reduced or something else, either way it makes the screen look like a cheap TV.

“Power saver” looks the worst, “Balanced” looks a bit better and “Performance mode” does not seem to affect the display and shows the true colors.

I am using GNOME, this however affects KDE too and presumably other desktops as well.

From what I understand, this is caused by a new default in power-profiles-daemon:

Panel power savings

Laptops with integrated Radeon graphics have a dedicated hardware function
to decrease panel power consumption in exchange for color accuracy. This
function is used when the system is on battery and the user has selected
the “balanced” or “power-saver” profiles.

If you decide that you don’t like how this behaves, you can disable the function
in one of two ways:

  1. Adding amdgpu.abmlevel=0 to the kernel command line. This will disable abm
    value changes entirely.
  2. By using POWER_PROFILE_DAEMON_ACTION_BLOCK=amdgpu_panel_power in the
    power-profiles-daemon environment as described below. This will allow you to
    still change values manually in sysfs but power-profiles-daemon will not
    change anything.

Citation above is from here: README.md: Add documentation for panel power savings (126f7d3a) · Commits · upower / power-profiles-daemon · GitLab

Personally, I consider this an anti-feature. I am an animator and need to see the correct colors regardless of the power profile.

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There is competition among vendors to reduce power consumption in linux. If your use case differs from call-center cubicle farms and mobile enterprise users, you need adjust. All linux users benefit when large enterprises expand their use of linux outside data centers, but there will be collateral damage for some.

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Wow, I actually realized it this morning when my laptop battery went to about 20% ( auto Power Saver ) I quickly changed it but did note that it looked “Desaturated” or “Washed Out”. I’m testing my HUION Drawing Tablet, so this morning in a rush to leave I did note that.

I was plugged up to power all day so this did not occur, but the colors are very desaturated. So much so that my Matcha Theme’s Green looked Teal and flat.

Glad you posted this, although for discoverability I’ll change the title a bit.

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This is not user friendly either. There are already two discussion threads on this issue; normal users are not aware that it’s related to the power-profiles-daemon, and they cannot adjust their color profiles directly through GUI.

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In hindsight, I’m glad I was not in Inkscape of Blender ! I would have been confused or angry !

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There is an active merge request on the PPD GitHub that seems to reduce this issue when the battery level is sufficient:

Perhaps we could provide some feedback to the developers?

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AMD can’t power-manage their own chips properly, so now they turn to silently altering colors on 3rd-party displays as if that’s a well-known source of power usage.

I don’t pay for hardware to beta-test, especially for free, albeit it’s more regular users praising AMD GPUs on Linux. The GPU needs to render what I want accurately; let my display handle it’s own color management, or the OS handling color profiles.

Can AMD on Linux even change HDMI colorspace yet without an EDID overrride? That wasn’t implemented for years after radeonsi → amdgpu.

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This is a rather bad update, I see this as a regression.

My display has 100% DCI-P3 color space and with this update it looks really bad when using power saving mode.

Even worse, the lack of communicating such a change. I would count myself a skilled Linux user, but this change kind of tricked me and actually made me think my laptop or screen is somehow broken.

I don’t see a progressive panel power savings adjustment makes this better. Additionally, I wonder how much power in terms of runtime one actually saves with this change. I doubt it is a lot and I doubt it justifies that change but I would love to see some stats.

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