ok. i think i fixed the screen flickering issue.
for me, i only needed one change in /etc/default/grub, adding i915.enable_psr=0
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i915.enable_psr=0"
- the best documentation about this might be in the Arch Linux wiki on Screen flickering from Panel Self Refresh (PSR)
- i got to the above from kernel - Flickering screen + CPU pipe B FIFO underrun when I use the termnal - Ask Ubuntu
- and this may also be useful, although the part about
intel_idle.max_cstate=4didn’t specifically help me [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun - this bug report has the most complete list of settings to test https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1550779
- intel_idle.max_cstate=4
- i915.enable_psr=0
- i915.enable_dc=0
- i915.enable_fbc=0
- i915.enable_dp_mst=0
it looks like i still have some of these errors in the nvidia-bug-report output
Sep 25 13:54:20 alan-gaming /usr/lib/gdm3/gdm-x-session[1672]: (EE) client bug: timer event11 debounce short: scheduled expiry is in the past (-15ms), your system is too slow
but no more kernel errors.