I installed KDE stable on my laptop, and the screen seems to flicker. I tried to take a video clip to show the problem, but it turned out to be quite hard to capture the flickering, so I have to rely on words. The flickering is better described as backlight pulsing at high frequency, and is different from graphic glitches or screen tearing. It is not very visible if I look at the screen directly, but rather visible and distracting using peripheral vision. Using free or non-free graphics drivers does not seem to matter - the flickering persists. I’m not sure if this is related to drivers or backlight pwm control. Please give me some suggestions on how to track down the problem.
I’m experiencing two kinds of flickering. A high frequency flicker as mentioned above (which seems to only appear on the desktop), and a slow flicker - backlight changes slightly every second or so (which is visible in many apps).
$ inxi -Fxzc0 System: Host: yichi-pc Kernel: 4.19.13-1-MANJARO x86_64 bits: 64 compiler: gcc v: 8.2.1 Desktop: KDE Plasma 5.14.4 Distro: Manjaro Linux Machine: Type: Laptop System: Hewlett-Packard product: HP OMEN Pro 15 Notebook v: Type1ProductConfigId serial: <filter> Mobo: Hewlett-Packard model: 8104 v: 02.38 serial: <filter> UEFI: Insyde v: F.46 date: 11/12/2018 Battery: ID-1: BAT0 charge: 21.9 Wh condition: 60.4/60.4 Wh (100%) model: 13142 RR04058 status: Discharging CPU: Topology: Quad Core model: Intel Core i7-4720HQ bits: 64 type: MT MCP arch: Haswell rev: 3 L2 cache: 6144 KiB flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 41523 Speed: 998 MHz min/max: 800/2600 MHz Core speeds (MHz): 1: 998 2: 999 3: 998 4: 1002 5: 998 6: 998 7: 998 8: 1000 Graphics: Device-1: Intel 4th Gen Core Processor Integrated Graphics vendor: Hewlett-Packard driver: i915 v: kernel bus ID: 00:02.0 Device-2: NVIDIA GK107GLM [Quadro K1100M] driver: N/A bus ID: 01:00.0 Display: x11 server: X.Org 1.20.3 driver: intel resolution: 1920x1080~60Hz OpenGL: renderer: Mesa DRI Intel Haswell Mobile v: 4.5 Mesa 18.3.1 direct render: Yes Audio: Device-1: Intel Xeon E3-1200 v3/4th Gen Core Processor HD Audio vendor: Hewlett-Packard driver: snd_hda_intel v: kernel bus ID: 00:03.0 Device-2: Intel 8 Series/C220 Series High Definition Audio vendor: Hewlett-Packard driver: snd_hda_intel v: kernel bus ID: 00:1b.0 Sound Server: ALSA v: k4.19.13-1-MANJARO Network: Device-1: Intel Wireless 7260 driver: iwlwifi v: kernel port: 4040 bus ID: 09:00.0 IF: wlo1 state: up mac: <filter> Drives: Local Storage: total: 476.94 GiB used: 11.32 GiB (2.4%) ID-1: /dev/sda vendor: Samsung model: MZHPU512HCGL-000H1 size: 476.94 GiB Partition: ID-1: / size: 452.11 GiB used: 11.32 GiB (2.5%) fs: ext4 dev: /dev/sda1 ID-2: swap-1 size: 16.00 GiB used: 0 KiB (0.0%) fs: swap dev: /dev/sda2 Sensors: System Temperatures: cpu: 31.0 C mobo: N/A Fan Speeds (RPM): N/A Info: Processes: 216 Uptime: 7m Memory: 15.59 GiB used: 1.31 GiB (8.4%) Init: systemd Compilers: gcc: 8.2.1 Shell: bash v: 4.4.23 inxi: 3.0.28