Won't adjust brightness

Hello,

I installed Manjaro KDE on an old desktop, Dell Optiplex 9010, most things work fine. However, the screen’s brightness won’t ajust in any way, neither in the DE settings nor with terminal applications like xbacklight. The system kind of pretens like if it is adjusting the brightness, but the actual brightness is unchanged.

$ cat /sys/class/backlight/acpi_video0/brightness 
3

What could be wrong?

Thanks in advance.

:+1: Welcome to Manjaro! :+1:

Please read this:

and post some more information so we can see what’s really going on. Now we know the symptom of the disease, but we need some more probing to know where the origin lies…

  1. An inxi --admin --verbosity=7 --filter --no-host --width would be the minimum required information… (Personally Identifiable Information like serial numbers and MAC addresses will be filtered out by the above command)

  2. What does:

    echo 10 | sudo tee /sys/class/backlight/acpi_video0/brightness
    

    do?

  3. What’s the output of:

     grep GRUB_CMDLINE_LINUX_DEFAULT /etc/default/grub
    

:thinking:

P.S. If you enter a bit more details in your profile, we can also see which Desktop Environment you’re using, which CPU/GPU you have, …

It seems like you expect me to know about all these crazy-complicated commands, but very few people do. Please just ask when you need information, but there is no way someone who is not an IT professional could know about all your requirements.

I will answer your questions 1, 2 and 3 when I get home.

If you find it a problem that my profile has too little information, you should probably talk to the administrators of these forums, not me, if they could add the requirements you ask for. In the meanwhile, there is nothing I can do, since I have no idea exactly what information you are asking for on my profile.

After you’ve come home, after you’ve provided the requested information and while you wait for someone to answer, please read this:

:innocent:

I’m finally home. Your howto-post is not relevant for me as I’ve never been a wizard at Windows. Also, being a Manjaro power user in order to use this forum should not be necessary.

$ inxi --admin --verbosity=7 --filter --no-host --width
System:
  Kernel: 5.10.7-3-MANJARO x86_64 bits: 64 compiler: gcc v: 10.2.1 
  parameters: BOOT_IMAGE=/boot/vmlinuz-5.10-x86_64 
  root=UUID=5a0d50ac-2042-4891-9af1-3a8a7b665d86 rw quiet apparmor=1 
  security=apparmor udev.log_priority=3 
  Desktop: KDE Plasma 5.20.5 tk: Qt 5.15.2 wm: kwin_x11 dm: SDDM 
  Distro: Manjaro Linux 
Machine:
  Type: Desktop System: Dell product: OptiPlex 9010 v: 01 serial: <filter> 
  Chassis: type: 15 serial: <filter> 
  Mobo: Dell model: 051FJ8 v: A01 serial: <filter> UEFI: Dell v: A12 
  date: 01/10/2013 
Battery:
  Device-1: hidpp_battery_0 model: Logitech Wireless Keyboard K540/K545 
  serial: <filter> charge: 100% (should be ignored) rechargeable: yes 
  status: Discharging 
  Device-2: hidpp_battery_1 model: Logitech Wireless Mouse M510 
  serial: <filter> charge: 55% (should be ignored) rechargeable: yes 
  status: Discharging 
Memory:
  RAM: total: 7.66 GiB used: 2.69 GiB (35.1%) 
  RAM Report: permissions: Unable to run dmidecode. Root privileges required. 
CPU:
  Info: Quad Core model: Intel Core i5-3470 bits: 64 type: MCP 
  arch: Ivy Bridge family: 6 model-id: 3A (58) stepping: 9 microcode: 21 
  L2 cache: 6 MiB bogomips: 25548 
  Speed: 1597 MHz min/max: 1600/3600 MHz Core speeds (MHz): 1: 1597 2: 1596 
  3: 1597 4: 1597 
  Flags: acpi aes aperfmperf apic arat arch_perfmon avx bts clflush cmov 
  constant_tsc cpuid cpuid_fault cx16 cx8 de ds_cpl dtes64 dtherm dts epb ept 
  erms est f16c flexpriority flush_l1d fpu fsgsbase fxsr ht ibpb ibrs ida 
  lahf_lm lm mca mce md_clear mmx monitor msr mtrr nonstop_tsc nopl nx pae pat 
  pbe pcid pclmulqdq pdcm pebs pge pln pni popcnt pse pse36 pti pts rdrand 
  rdtscp rep_good sep smep smx ss ssbd sse sse2 sse4_1 sse4_2 ssse3 stibp 
  syscall tm tm2 tpr_shadow tsc tsc_deadline_timer vme vmx vnmi vpid x2apic 
  xsave xsaveopt xtopology xtpr 
  Vulnerabilities: Type: itlb_multihit status: KVM: VMX disabled 
  Type: l1tf 
  mitigation: PTE Inversion; VMX: conditional cache flushes, SMT disabled 
  Type: mds mitigation: Clear CPU buffers; SMT disabled 
  Type: meltdown mitigation: PTI 
  Type: spec_store_bypass 
  mitigation: Speculative Store Bypass disabled via prctl and seccomp 
  Type: spectre_v1 
  mitigation: usercopy/swapgs barriers and __user pointer sanitization 
  Type: spectre_v2 mitigation: Full generic retpoline, IBPB: conditional, 
  IBRS_FW, STIBP: disabled, RSB filling 
  Type: srbds status: Vulnerable: No microcode 
  Type: tsx_async_abort status: Not affected 
Graphics:
  Device-1: Intel Xeon E3-1200 v2/3rd Gen Core processor Graphics vendor: Dell 
  driver: i915 v: kernel bus ID: 00:02.0 chip ID: 8086:0152 
  Display: x11 server: X.Org 1.20.10 compositor: kwin_x11 driver: 
  loaded: intel display ID: :0 screens: 1 
  Screen-1: 0 s-res: 1920x1080 s-dpi: 96 s-size: 508x285mm (20.0x11.2") 
  s-diag: 582mm (22.9") 
  Monitor-1: HDMI2 res: 1920x1080 dpi: 81 size: 600x340mm (23.6x13.4") 
  diag: 690mm (27.2") 
  OpenGL: renderer: Mesa DRI Intel HD Graphics 2500 (IVB GT1) 
  v: 4.2 Mesa 20.3.3 compat-v: 3.0 direct render: Yes 
Audio:
  Device-1: Intel 7 Series/C216 Family High Definition Audio vendor: Dell 
  driver: snd_hda_intel v: kernel bus ID: 00:1b.0 chip ID: 8086:1e20 
  Sound Server: ALSA v: k5.10.7-3-MANJARO 
Network:
  Device-1: Intel 82579LM Gigabit Network vendor: Dell driver: e1000e 
  v: kernel port: f080 bus ID: 00:19.0 chip ID: 8086:1502 
  IF: eno1 state: up speed: 100 Mbps duplex: full mac: <filter> 
  IP v4: <filter> type: dynamic noprefixroute scope: global 
  broadcast: <filter> 
  IP v6: <filter> type: noprefixroute scope: link 
  WAN IP: <filter> 
RAID:
  Hardware-1: Intel SATA Controller [RAID mode] driver: ahci v: 3.0 port: f060 
  bus ID: 00:1f.2 chip ID: 8086.2822 rev: 04 
Drives:
  Local Storage: total: 465.76 GiB used: 86.8 GiB (18.6%) 
  SMART Message: Unable to run smartctl. Root privileges required. 
  ID-1: /dev/sda maj-min: 8:0 vendor: Seagate model: ST500DM002-1BD142 
  size: 465.76 GiB block size: physical: 4096 B logical: 512 B speed: 6.0 Gb/s 
  serial: <filter> rev: KC47 
  Optical-1: /dev/sr0 vendor: TSSTcorp model: DVD+-RW SN-208BB rev: D500 
  dev-links: cdrom 
  Features: speed: 24 multisession: yes audio: yes dvd: yes 
  rw: cd-r,cd-rw,dvd-r,dvd-ram state: running 
Partition:
  ID-1: / raw size: 228.33 GiB size: 223.75 GiB (97.99%) 
  used: 86.8 GiB (38.8%) fs: ext4 dev: /dev/sda4 maj-min: 8:4 label: N/A 
  uuid: 5a0d50ac-2042-4891-9af1-3a8a7b665d86 
  ID-2: /boot/efi raw size: 300 MiB size: 299.4 MiB (99.80%) 
  used: 416 KiB (0.1%) fs: vfat dev: /dev/sda1 maj-min: 8:1 label: N/A 
  uuid: 3899-63A9 
Swap:
  Kernel: swappiness: 60 (default) cache pressure: 100 (default) 
  ID-1: swap-1 type: partition size: 8.8 GiB used: 0 KiB (0.0%) priority: -2 
  dev: /dev/sda3 maj-min: 8:3 label: N/A 
  uuid: b6e364b0-9b01-464c-994a-987555562a54 
Unmounted:
  ID-1: /dev/sda2 maj-min: 8:2 size: 228.33 GiB fs: ext4 label: N/A 
  uuid: 0dd75152-ca35-4253-ad27-a32839371a6d 
USB:
  Hub-1: 1-0:1 info: Full speed (or root) Hub ports: 2 rev: 2.0 
  speed: 480 Mb/s chip ID: 1d6b:0002 
  Hub-2: 1-1:2 info: Intel Integrated Rate Matching Hub ports: 6 rev: 2.0 
  speed: 480 Mb/s chip ID: 8087:0024 
  Hub-3: 2-0:1 info: Full speed (or root) Hub ports: 2 rev: 2.0 
  speed: 480 Mb/s chip ID: 1d6b:0002 
  Hub-4: 2-1:2 info: Intel Integrated Rate Matching Hub ports: 8 rev: 2.0 
  speed: 480 Mb/s chip ID: 8087:0024 
  Hub-5: 3-0:1 info: Full speed (or root) Hub ports: 4 rev: 2.0 
  speed: 480 Mb/s chip ID: 1d6b:0002 
  Device-1: 3-1:2 info: Logitech Unifying Receiver type: Keyboard,Mouse,HID 
  driver: logitech-djreceiver,usbhid interfaces: 3 rev: 2.0 speed: 12 Mb/s 
  chip ID: 046d:c52b 
  Device-2: 3-2:3 info: Cambridge Silicon Radio Bluetooth Dongle (HCI mode) 
  type: Bluetooth driver: btusb interfaces: 2 rev: 2.0 speed: 12 Mb/s 
  chip ID: 0a12:0001 
  Hub-6: 4-0:1 info: Full speed (or root) Hub ports: 4 rev: 3.0 speed: 5 Gb/s 
  chip ID: 1d6b:0003 
Sensors:
  System Temperatures: cpu: 29.8 C mobo: 27.8 C 
  Fan Speeds (RPM): N/A 
Info:
  Processes: 179 Uptime: 57m wakeups: 12 Init: systemd v: 247 Compilers: 
  gcc: 10.2.0 Packages: 1301 pacman: 1295 lib: 390 flatpak: 6 Shell: Bash 
  v: 5.1.0 running in: yakuake inxi: 3.2.02


$ echo 10 | sudo tee /sys/class/backlight/acpi_video0/brightness
[sudo] passord for jonas: 
10


$ grep GRUB_CMDLINE_LINUX_DEFAULT /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="quiet apparmor=1 security=apparmor udev.log_priority=3"

I’m not expecting you to be if you don’t want to, but at least I’m expecting you to provide the information requested:

:man_shrugging:

Easy to miss at the bottom, took me a while to realise it was there. :slight_smile:

This didn’t change the brightness?

If no,

  1. add acpi_backlight=vendor to the end of the line GRUB_CMDLINE_LINUX_DEFAULT="quiet apparmor=1 security=apparmor udev.log_priority=3 in file /etc/default/grub
  2. Reboot
  3. Try again.

If yes: don’t do the above and shout out.

:crossed_fingers:

Thanks! I did all the steps. Unfortunately it still doesn’t work.

I won’t be able to help you any further then, sorry!

:sob:

Thank you for trying!

1 Like