When using my laptop, the screen will flicker. It definitely happens during “low usage” points, like web-browsing / entering this comment in a forum. I have not yet been able to confirm whether it happens under heavier load / while gaming. Like these threads:
a. [redacted due to link limit] /geforce/forums/user/633273/407871/upper-part-of-the-screen-extremely-randomly-flicke/
b. [redacted due to link limit] /geforce/forums/geforce-graphics-cards/5/405393/1660-super-top-screen-flickering/?topicPage=11%2F
Hopefully this is not a “faulty GPU / faulty video memory chips” problem like posited in this ask ubuntu anwer? [redacted due to link limit] /1300922/ubuntu-20-04-nvidia-gtx-1660-super-screen-flickering
How can I fix these two problems?
$ sudo nvidia-smi
Fri Sep 24 17:21:23 2021
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 470.63.01 Driver Version: 470.63.01 CUDA Version: 11.4 |
|-------------------------------+----------------------+----------------------+
| GPU Name Persistence-M| Bus-Id Disp.A | Volatile Uncorr. ECC |
| Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. |
| | | MIG M. |
|===============================+======================+======================|
| 0 NVIDIA GeForce ... Off | 00000000:01:00.0 Off | N/A |
| N/A 45C P8 11W / N/A | 341MiB / 5946MiB | 5% Default |
| | | N/A |
+-------------------------------+----------------------+----------------------+
+-----------------------------------------------------------------------------+
| Processes: |
| GPU GI CI PID Type Process name GPU Memory |
| ID ID Usage |
|=============================================================================|
| 0 N/A N/A 1282 G /usr/lib/xorg/Xorg 45MiB |
| 0 N/A N/A 1729 G /usr/lib/xorg/Xorg 121MiB |
| 0 N/A N/A 1900 G /usr/bin/gnome-shell 92MiB |
| 0 N/A N/A 2909 G ...AAAAAAAAA= --shared-files 52MiB |
| 0 N/A N/A 3194 G ...AAAAAAAAA= --shared-files 18MiB |
+-----------------------------------------------------------------------------+
$ uname -a
Linux gaming 5.11.0-36-generic #40~20.04.1-Ubuntu SMP Sat Sep 18 02:14:19 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
Please let me know if there are any further details I should provide.
i’m not sure why typing seems to be the best way to cause this flickering. it happens not just in Google Chrome (as in the video above), but also in vi in a terminal window.
other usage of the laptop (e.g. not doing anything but staring at the screen, or just using the mouse) don’t seem to cause the flickering nearly as frequently
[ETA2]
there were a few of these errors in the attached bug report log
Sep 25 07:48:53 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (EE) client bug: timer event13 debounce: scheduled expiry is in the past (-6ms), your system is too slow
Sep 25 07:48:53 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (EE) client bug: timer event13 debounce short: scheduled expiry is in the past (-19ms), your system is too slow
and i see that there are a lot of them in /var/log/syslog, as well as some kernel errors
$ sudo cat /var/log/syslog | grep -E "gdm|kernel"
Sep 25 08:26:53 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (EE) client bug: timer event13 debounce: scheduled expiry is in the past (-12ms), your system is too slow
Sep 25 08:26:53 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (EE) client bug: timer event13 debounce short: scheduled expiry is in the past (-25ms), your system is too slow
Sep 25 08:26:57 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (EE) client bug: timer event13 debounce: scheduled expiry is in the past (-6ms), your system is too slow
Sep 25 08:26:57 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (EE) client bug: timer event13 debounce short: scheduled expiry is in the past (-19ms), your system is too slow
Sep 25 08:27:01 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (EE) client bug: timer event13 debounce: scheduled expiry is in the past (-4ms), your system is too slow
Sep 25 08:27:01 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (EE) client bug: timer event13 debounce short: scheduled expiry is in the past (-17ms), your system is too slow
Sep 25 08:28:41 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (--) NVIDIA(GPU-0): DFP-0: disconnected
Sep 25 08:28:41 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (--) NVIDIA(GPU-0): DFP-0: Internal TMDS
Sep 25 08:28:41 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (--) NVIDIA(GPU-0): DFP-0: 165.0 MHz maximum pixel clock
Sep 25 08:28:41 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (--) NVIDIA(GPU-0):
Sep 25 08:28:41 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (--) NVIDIA(GPU-0): DFP-0: disconnected
Sep 25 08:28:41 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (--) NVIDIA(GPU-0): DFP-0: Internal TMDS
Sep 25 08:28:41 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (--) NVIDIA(GPU-0): DFP-0: 165.0 MHz maximum pixel clock
Sep 25 08:28:41 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (--) NVIDIA(GPU-0):
Sep 25 08:29:41 alan-gaming /usr/lib/gdm3/gdm-x-session[1728]: (EE) client bug: timer event13 debounce short: scheduled expiry is in the past (-1ms), your system is too slow
Sep 25 08:29:51 alan-gaming kernel: [ 2487.889834] DMAR: DRHD: handling fault status reg 3
Sep 25 08:29:51 alan-gaming kernel: [ 2487.889845] DMAR: [DMA Read] Request device [00:02.0] PASID ffffffff fault addr 124ea7000 [fault reason 06] PTE Read access is not set
Sep 25 08:29:56 alan-gaming kernel: [ 2493.348431] DMAR: DRHD: handling fault status reg 3
Sep 25 08:29:56 alan-gaming kernel: [ 2493.348453] DMAR: [DMA Read] Request device [00:02.0] PASID ffffffff fault addr 124ea7000 [fault reason 06] PTE Read access is not set
Sep 25 08:29:59 alan-gaming kernel: [ 2496.423692] DMAR: DRHD: handling fault status reg 3
Sep 25 08:29:59 alan-gaming kernel: [ 2496.423705] DMAR: [DMA Read] Request device [00:02.0] PASID ffffffff fault addr 124ea7000 [fault reason 06] PTE Read access is not set
Sep 25 08:30:02 alan-gaming kernel: [ 2499.232186] DMAR: DRHD: handling fault status reg 3
Sep 25 08:30:02 alan-gaming kernel: [ 2499.232198] DMAR: [DMA Read] Request device [00:02.0] PASID ffffffff fault addr 124ea7000 [fault reason 06] PTE Read access is not set
Sep 25 08:30:02 alan-gaming kernel: [ 2499.637603] DMAR: DRHD: handling fault status reg 2
Sep 25 08:30:02 alan-gaming kernel: [ 2499.637615] DMAR: [DMA Read] Request device [00:02.0] PASID ffffffff fault addr 124ea7000 [fault reason 06] PTE Read access is not set
Sep 25 08:30:03 alan-gaming kernel: [ 2499.943519] DMAR: DRHD: handling fault status reg 3
Sep 25 08:30:03 alan-gaming kernel: [ 2499.943547] DMAR: [DMA Read] Request device [00:02.0] PASID ffffffff fault addr 124ea7000 [fault reason 06] PTE Read access is not set
Sep 25 08:30:11 alan-gaming kernel: [ 2508.234806] DMAR: DRHD: handling fault status reg 2
Sep 25 08:30:11 alan-gaming kernel: [ 2508.234817] DMAR: [DMA Read] Request device [00:02.0] PASID ffffffff fault addr 124ea7000 [fault reason 06] PTE Read access is not set
Sep 25 08:30:12 alan-gaming kernel: [ 2509.710031] DMAR: DRHD: handling fault status reg 3
Sep 25 08:30:12 alan-gaming kernel: [ 2509.710044] DMAR: [DMA Read] Request device [00:02.0] PASID ffffffff fault addr 124ea7000 [fault reason 06] PTE Read access is not set
this line may be relevant, as to which device is 00:02.00 – being the CPU (i915)
Sep 25 07:48:54 alan-gaming kernel: i915 0000:00:02.0: [drm] *ERROR* CPU pipe A FIFO underrun
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
Very good!
So, it seems your monitor is using the intell graphics card and not the nvidia.
I have no flickering in my system (in none of the three displays) but I have not configured anything about grub. The only other configuration I have made is to put the noveau driver in black list:
NOTE: I think I have experienced some flickering when using Gnome but now that I’ve successfully configured the I3wm (I use it as a default), I have not experienced any flickering nor any other display issues.