Same regression here on a different RDNA4 card and a higher-bandwidth display.
GPU: Radeon AI PRO R9700 (gfx1201) Display: LG UltraFine 5120×2160 @ 120 Hz over DisplayPort (DSC) Ubuntu 26.04, GNOME 50.1 Wayland, Mesa 26.0.8 Findings: 7.0.0-31: no issue. 7.0.0-38: flashes. When one hits, the window underneath briefly shows through the window on top (for example, VS Code text visible through Firefox). 100 Hz does not help here, unlike in the original report. That's probably because 5K needs far more bandwidth. amdgpu.dcdebugmask=0x10 (overlay planes off) does not help. echo high > /sys/class/drm/card1/device/power_dpm_force_performance_level stops it completely. So does running a GNOME screen recording, which keeps the GPU busy. At idle, MCLK sits at DPM level 0 (96 MHz) on both kernels. The regression looks related to MCLK switching, possibly interacting with the flip and damage-handling changes in -38 already listed above. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2169319 Title: amdgpu: screen flashes at 120/144 Hz on RX 9060 XT (gfx1200), regression 7.0.0-34 -> 7.0.0-38 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2169319/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
