T400 LCD brightness unstable

My T400 has been used only 1.5 years, but its LCD brightness suddenly became unstable the day before yesterday, and the screen also turns a little red, the indictor lights turn from green to a little orange color. I tried to find the reason and found maybe the LCD cable doesn't have a good contact, so I tried to re set it. But the problem is still here. Why? What's the problem? How to fix it?

The indicator lights are just a green LED... There's no way they can all turn orange.
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Similar Messages

T400 LCD problem

hi guys, my t400 lcd does not included led backlight, and i feel it is terribly dim compare to other notebook such as compaq v3000 and hp dv2000, what is going on? i heard someone said t400 lcd without led backlight are good too, but my lcd seems dim even though i switch to screen brightness to the max, it is not totally dark but it looks dim, can you guys help me?

also do you have the switchable graphics card version? if so switch to intel by going to the power saving mode, and see whether the internal LCD still have this problem.
But what you are describing sounds like an issue with the LCD panel itself, you can get a new LCD for around 150 to 200 dollars on the net.
Regards,
Jin Li
May this year, be the year of 'DO'!
I am a volunteer, and not a paid staff of Lenovo or Microsoft

Laptop-mode-tools no longer adjusts LCD brightness

I just discovered that laptop-mode-tools no longer adjusts the brightness of the LCD when switched to battery. This is not a general issue. laptop-mode is active on battery (as well as being enabled via the systemd service), the computer knows it is on battery (checking with on_ac_power and reading from /sys/class/power_supply/*/* give the expected results) and other things are correctly adjusted e.g. bluetooth is blocked with rfkill. Moreover, as root I can adjust the brightness in the usual way by hand:
echo 10 >| /sys/class/backlight/acpi_video0/brightness
works just fine. The >| is needed because for interactive shell's, root's .bashrc sets noclobber. This obviously doesn't affect laptop-mode tools because it doesn't run an interactive shell. In contrast:
$ cat /etc/laptop-mode/conf.d/lcd-brightness.conf | grep -v "^#"
DEBUG=1
CONTROL_BRIGHTNESS=1
BATT_BRIGHTNESS_COMMAND="echo 7"
LM_AC_BRIGHTNESS_COMMAND="echo 10"
NOLM_AC_BRIGHTNESS_COMMAND="echo 12"
BRIGHTNESS_OUTPUT="/sys/class/backlight/acpi_video0/brightness"
DEBUG wasn't 1 when the problem started. I tried setting it to get more info but haven't found anything more in the journal/logs.
KDE is set to not touch the default brightness at all. All it does is (further) dim the display after so many minutes depending on the power supply and status.
This did work fine but I haven't been on battery for a while so I'm not sure when exactly it stopped working. My brightness is set by default to 12 on boot or wake from sleep which suggests laptop-mode tools does something or something else is now handling this which I'm not aware of. But the switch to battery does not trigger any alteration in the brightness and laptop-mode status does not even mention LCD brightness as one of the things laptop-mode tools controls.
Have I missed a change in how this is handled somewhere?

I doubt this is related but it is currently my only lead so here goes. I set the LCD brightness control for debug so I've been trying to watch it. However, so far it is all smiles e.g. on boot it all works fine and says so.
However, I found I'm getting another error on boot which is
/usr/share/laptop-mode-tools/modules/pcie-aspm: line 10: write error: Operation not permitted
Note that I copied that by eye from VT1 so if a colon is out of place, that's why.
The contents of that file is:
#! /bin/sh
# Laptop mode tools module: PCIe Active State Power Management
if [ x$CONTROL_PCIE_ASPM = x1 ] || [ x$ENABLE_AUTO_MODULES = x1 -a x$CONTROL_PCIE_ASPM = xauto ]; then
if [ $ON_AC -eq 1 ]; then
log "VERBOSE" "On AC power: setting pcie_aspm to default"
if [ -f /sys/module/pcie_aspm/parameters/policy ]; then
echo default > /sys/module/pcie_aspm/parameters/policy
if [ $? -eq 0 ]; then
log "VERBOSE" "PCIe ASPM set to 'default'"
else
log "VERBOSE" "PCIe ASPM tweaking is prohibited by the kernel"
fi
else
log "VERBOSE" "PCIe ASPM is not available"
fi
else
log "VERBOSE" "On battery: setting pcie_aspm to powersave"
if [ -f /sys/module/pcie_aspm/parameters/policy ]; then
echo powersave > /sys/module/pcie_aspm/parameters/policy
if [ $? -eq 0 ]; then
log "VERBOSE" "PCIe ASPM set to 'powersave'"
else
log "VERBOSE" "PCIe ASPM tweaking is prohibited by the kernel"
fi
else
log "VERBOSE" "PCIe ASPM is not available"
fi
fi
else
log "VERBOSE" "PCIe ASPM power savings module is disabled"
fi
So I assume it is saying it cannot write to /sys/module/pcie_aspm/parameters/policy but the permissions etc. on that, at least, don't look strange:
l /sys/module/pcie_aspm/parameters/
total 0
drwxr-xr-x 2 root root 0 Gor 25 21:24 ./
drwxr-xr-x 3 root root 0 Gor 25 21:23 ../
-rw-r--r-- 1 root root 4.0K Gor 25 21:24 policy
Last edited by cfr (2013-07-25 20:47:13)

Sony Vaio FZ Series - LCD brightness

Hi All,
I have recently bought a Sony VAIO FZ11S and I've successfully installed Archlinux:
Fully working:
- CPU Scaling (using cpudyn)
- Multimedia keys (mute, volume up/down, play/stop, etc. using Xmodmap)
- Wireless (using iwl3945. Can't connect with AP with hidden SSID)
- Nvidia GeForce 8400M (using latest nvidia drivers with stock arch kernel 2.6.23)
- Audio (after adding 'options snd-hda-intel model=vaio' to /etc/modprobe.conf. MIC not tested yet)
Untested:
- bluetooth
- SD/MS card reader
- Video camera
NOT WORKING:
- LCD brightness adjustment: FN+F5/F6 are detected correctly by acpid but nothing happens. I'm using the module sony-laptop included with kernel 2.6. Folder /sys/class/backlight is empty. I can use nvidia-settings to change COLOR BRIGHTNESS but this is NOT a good solution IMHO. I'd like to get the same capabilities I get running Windows Vista. (change LCD backlight).
I've read somewhere it is a problem common to all laptop with the same NVIDIA videocard. Does anyone know a fix for this? I've also tried with latest nvidia beta drivers with no success.
- Hibernate/suspend. I tried with pm-tools to suspend/hibernate laptop but nothing is working correctly. I didn't investigate further. Has anyone got a quick solution for this?
lspci output:
00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub (rev 0c)
00:01.0 PCI bridge: Intel Corporation Mobile PM965/GM965/GL960 PCI Express Root Port (rev 0c)
00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Contoller #4 (rev 03)
00:1a.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 03)
00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 03)
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03)
00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 03)
00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 2 (rev 03)
00:1c.2 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 3 (rev 03)
00:1c.4 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 5 (rev 03)
00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 03)
00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 03)
00:1d.2 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 03)
00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f3)
00:1f.0 ISA bridge: Intel Corporation 82801HEM (ICH8M) LPC Interface Controller (rev 03)
00:1f.1 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) IDE Controller (rev 03)
00:1f.2 SATA controller: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) SATA AHCI Controller (rev 03)
00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 03)
01:00.0 VGA compatible controller: nVidia Corporation GeForce 8400M GT (rev a1)
06:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG Network Connection (rev 02)
08:00.0 Ethernet controller: Marvell Technology Group Ltd. 88E8036 PCI-E Fast Ethernet Controller (rev 16)
09:03.0 CardBus bridge: Texas Instruments PCIxx12 Cardbus Controller
09:03.1 FireWire (IEEE 1394): Texas Instruments PCIxx12 OHCI Compliant IEEE 1394 Host Controller
09:03.2 Mass storage controller: Texas Instruments 5-in-1 Multimedia Card Reader (SD/MMC/MS/MS PRO/xD)
Please help
V.
Last edited by Vins (2007-12-09 11:37:08)

I recently bought a Sony FZ180, almost identical stats and hardware.
I tried all the same suggestions, which worked fine on my old laptop, but will not for this one. If anyone can think of another method to control the backlight I would be grateful.
Also, I tested the SD slot, the TI driver recognizes when a card is inserted, but no devices or mount-points are created.
tifm_core: MMC/SD card detected in socket 0:1
tifm0 : demand removing card from socket 0:1
(The second line is from me removing the card, not a defective slot.)
Everything else works great, though. Arch boots to a full KDE desktop much, much faster than my cleaned-up vista partition. I'm really happy overall.

LCD Brightness, sony_acpi from aur won't build

I'm using a Sony VAIO vgn-sz430n, and the Fn keys won't work to change the brightness. I'm not so concerned about the Fn keys, for I've seen tons of documentation to get those working with xbindkeys, xmonad, openbox, etc. and I will worry about that later.
Most importantly, I cannot change the screen brightness. Xbacklight does not do anything, laptop-mode-tools and gnome/xfce4-power-manager do nothing. The screen brightness is always at the maximum.
I have an nvidia Geforce Go 7400 card with the proprietary nvidia driver
I read that I need the sony_acpi module, and I've been trying to install it from the AUR, but I get errors and I don't know what to do. I've tried with yaourt and manually. Here are the results from yaourt:
==> Building and installing package
==> Making package: sony_acpi 1-1 i686 (Sun Jun 14 14:56:12 CDT 2009)
==> Checking Runtime Dependencies...
==> Checking Buildtime Dependencies...
==> Retrieving Sources...
-> Found sony_acpi.tar.gz in build dir
==> Validating source files with md5sums...
sony_acpi.tar.gz ... Passed
==> Extracting Sources...
-> bsdtar -x -f sony_acpi.tar.gz
==> Removing existing pkg/ directory...
==> Entering fakeroot environment...
==> Starting build()...
make -C /lib/modules/2.6.29-ARCH/build SUBDIRS=/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi modules
make[1]: Entering directory `/usr/src/linux-2.6.29-ARCH'
CC [M] /tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi/sony_acpi.o
/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi/sony_acpi.c:55: warning: initialization from incompatible pointer type
/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi/sony_acpi.c: In function 'sony_walk_callback':
/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi/sony_acpi.c:253: error: dereferencing pointer to incomplete type
/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi/sony_acpi.c:255: error: dereferencing pointer to incomplete type
/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi/sony_acpi.c:256: error: dereferencing pointer to incomplete type
/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi/sony_acpi.c: In function 'sony_acpi_add':
/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi/sony_acpi.c:269: error: lvalue required as left operand of assignment
make[2]: *** [/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi/sony_acpi.o] Error 1
make[1]: *** [_module_/tmp/yaourt-tmp-agi/aur-sony_acpi/sony_acpi/src/sony_acpi] Error 2
make[1]: Leaving directory `/usr/src/linux-2.6.29-ARCH'
make: *** [default] Error 2
==> ERROR: Build Failed.
Aborting...
Error: Makepkg was unable to build sony_acpi package.
The strange thing is this works in other distributions, such as Ubuntu. If I fired up a live cd and tested out my Fn keys, the brightness would change and there would be an on screen display for feedback.
What is Ubuntu doing, specifically, that Arch is not doing? Is there any way I could load an ubuntu live cd and then find what files/programs/modules/whatever are in place that allow brightness changes? Does anyone know this offhand?
Help!

I have Sony Vaio VGN-FZ38M with Nvidia 8400M GT. I used package 'nvclock' (it is in repo) to control lcd brightness, here site with more info: NVClock. Some time ago I also configured Fn keys to work with it (on Ubuntu), but on Arch I didn't manged but I didn't try hard (in general i don't need, my laptop is stationary all the time). Solution I've found somwehere in Ubuntu forums.
edit: typo in address
edit2:
here's the solution from Ubuntu: http://newyork.ubuntuforums.org/showthr … ?t=1004568
Last edited by folletto (2009-06-14 20:58:56)

Laptop-mode / laptop-mode-tools lcd brightness issue

I have an issue with my lcd brightness config in laptop-mode tools
here is the brightness values
[venky@ARCHROCKS ~]$ cat /proc/acpi/video/VID/LCD/brightness
levels: 72 24 12 24 36 48 60 72 84 100
current: 72
[venky@ARCHROCKS ~]$
following is my lcd-bightness.conf file under /etc/laptop-mode/conf.d
# Configuration file for Laptop Mode Tools module lcd-brightness.
# For more information, consult the laptop-mode.conf(8) manual page.
# LCD brightness settings
# Using these settings, you can make laptop mode tools automatically adjust
# your LCD's brightness settings. The settings are extremely simple -- they
# only allow for the execution of a command, nothing more. The reason for this
# is that LCD brightness settings are very different between laptop vendors.
# Suggestions for commands:
# * If your system has the file "/proc/acpi/video/VID/LCD/brightness" (VID may
# be VID1 or similar), use this file as BRIGHTNESS_OUTPUT, and use
# the command "echo <value>". The possible values can be listed using the
# command:
# cat /proc/acpi/video/VID/LCD/brightness
# * If you have a file /sys/class/backlight/.../brightness, then you can use
# that file as BRIGHTNESS_OUTPUT, and the command "echo <value>".
# As far as I understand it the values are between 0 and
# the value contained in the file /sys/class/backlight/.../max_brightness.
# * For Toshiba laptops, use the command "toshset" with the -lcd or -inten
# command. Read the toshset(1) manual page for more information on the
# parameters for this command. If you use this command, set
# BRIGHTNESS_OUTPUT to "/dev/null".
# IMPORTANT: In versions 1.36 and earlier, these settings were included in the
# main laptop-mode.conf configuration file. If they are still present, they
# overrule the settings in this file. To fix this, simply delete the settings
# from the main config file.
# Should laptop mode tools control LCD brightness?
CONTROL_BRIGHTNESS=1
# Commands to execute to set the brightness on your LCD
BATT_BRIGHTNESS_COMMAND="echo 24"
LM_AC_BRIGHTNESS_COMMAND="echo 100"
NOLM_AC_BRIGHTNESS_COMMAND="echo 72"
BRIGHTNESS_OUTPUT="/proc/acpi/video/VID/LCD/brightness"
so basically while in AC power i want full brightness when on battery i want one notch more than the minimum brightness and when laptop-mode is not running i want 2 notches less than maximum brightness.
the battery mode works fine when i unplug the computer but when i replug the AC power it goes to 72 instead of 100. I mean laptop mode is running coz when I remove ac power it goes to 24 again.
Am I doing something wrong?

When you plug in AC power, laptop-mode probably turns down, so LCD brightness is set to 72. It depends on if you have set in /etc/laptop-mode/laptop-mode.conf ENABLE_LAPTOP_MODE_ON_AC to 0 or 1.

Thinkpad T400 LCD problem

Dear Lenovo Expertise,
My thinkpad is T400; 7417-CTO.
For past one wk, their is a constant "thin yellow" line in the right corner of LCD. It sometimes disappears when I press corner of LCD. But still it re-appears. Its driving me nuts.
Pls tell me what to do. Do i need to replace it ?
Regards,
Dr. Khan

Try eBay:- T400 LCD
Marketplace of forum.thinkpads.com • Index page is another alternative, personally I recommend the forum as I have bought quite a few things from there.
Hope it helps.
Maliha (I don't work for lenovo)
ThinkPads:- T400[Win 7], T60[Win 7], IBM 240[Win XP]
IdeaPad: U350
Apple:- Macbook Air [Snow Leopard]
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[SOLVED] Setting LCD brightness in terminal

I'm trying to set LCD brightness in script. But unfortunately the desired command do not work.
I've grepped my VGA card number
01:05.0 VGA compatible controller: ATI Technologies Inc RS780M/RS780MN [Radeon HD 3200 Graphics]
"setpci -s 01:05.0 F4.B=F0" do not change the brightness whatever value I use.
My pc is a thinkpad laptop. If there is any workaround?
Last edited by tasty_minerals (2011-10-12 20:13:37)

roygbiv wrote:
I used this script binded with two keys:
#!/bin/bash
file="/sys/class/backlight/acpi_video0/brightness"
level=$(cat $file)
if [[ "$#" -eq 0 ]]; then
cat $file
elif [[ "$1" = "-" ]]; then
echo $(( level - 1 )) > $file
elif [[ "$1" = "+" ]]; then
echo $(( level + 1 )) > $file
fi
By adding the location of the script to root's $PATH, i.e $HOME/myscripts, it can be run with sudo. It accepts '+' and '-', but it can easily be changed to handle brightness [0-24] values I guess.
thanks again, will try it out

T400 LCD TFT display specifications

Hey everyone,
I was wondering if anyone would have on hand or know where to find information on the display specifications for the T400 LCD TFT display (WXGA, LED backlight).
Specifically I'm looking for:
Model Name/Manufacturer:
Display area:
Pixel Pitch:
Synchronization
Horizontal: (kHz)
Vertical: (Hz)
Display Color: (24bit, 16bit)
Cheers,
J

Welcome to the forum!
Do I understand correctly that you bought a complete new LCD Assembly? Do you have proof from the seller that it was working properly before you bought it?
Can you see a picture if you use a torchlight over the panel?
A faint dark picture could be a defective LCD cable, inverter/LED card or a defective LCD backlight. Since you see a picture I would rule out a motherboard fuse problem.
Edit: Richk was faster!
/L40SX/240/240X/2*340CSE/360PE/365XD/380D/380E/380XD/380Z/390/560E/560X/2*570/2*600/600E/750Cs/755C/760CD/760EL/760XD/770E/A20p/A22p
A31/i1600/G40/R50p/R61i/S30/SL510/2*T22/4*T4x/11*T6x/6*T4x0x/6*T5x0/3*W5x0/W700/3*X2x/4*X3x/3*X4x/5*X6x/3*X6xT/10*X2xx/2*X200T/4*X30x/Z60m/3*Z61x
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T400 screen brightness frequently resets

My T400 screen brightness resets to its lowest value intermittently. Sometimes it takes only 30 seconds, sometimes it's several minutes. If I press a key, it goes back to the bright setting. I didn't intentionally change any power or screen settings, and none of the settings I can find (Windows or ThinkVantage power settings) indicate that this should happen.
Any idea what's going on?
Thanks.
Message Edited by allanbracker on 08-11-2009 10:44 AM

@Jeffw3030,
try this.
http://forums.lenovo.com/t5/T400-T500-and-newer-T-series/T410-Screen-flickering-randomly-screen-cont...
//JameZ
Check out the Community Knowledge Base for hints and tips.
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If you find a post helpful and it answers your question, please mark it as an "Accepted Solution"!
X240 | 8GB RAM | 512GB Samsung SSD

T400 LCD Screen has a dark piont within half year.

T400 LCD has a dark point within half year, which I bought Oct. 2008. Could I get some change or warranty?

welcome to the forum!
you'll need to reference your defective pixel(s) with the current replacement policy to know if it falls under warranty:
http://www-307.ibm.com/pc/support/site.wss/MIGR-69856.html
ThinkStation C20
ThinkPad X1C · X220 · X60T · s30 · 600

Bulge on the upper right of T400 LCD bezel

Hi all,
Recently I notice there is a small bulge on the upper right of my T400 lcd bezel, specifically near the opening claw there. Is this normal ? I have been using for a month I jst notice it recently.
Thanks a lot

Hi,
Sorry for the late reply was away for a few days. Attached image.. Pls comment. Its nothing big, however its annoying once found out
Sorry the pic is low quality took it from my mobile phone
Link to Picture
Before, see the 2nd pic and you will notice the gap will close once I press them
Link to Picture
After I close
Thank you in advance
Moderator Note; pictures >50K converted to links. Forum Rules
Message Edited by andyP on 08-06-2009 09:15 PM

I fixed the LCD Brightness in my Samsung NP300 Laptop

tl;dr: acpi_backlight=vendor to kernel at boot (add in grub configuration) + modprobe -r samsung_laptop && systemctl restart gdm. (i discovered it with pf-kernel, need to try in stock kernel)
Well, i don't know if this is known, but i could not find it.
Maybe its a bug to be fixed that im not aware of.
Well, i had the common problem with the LCD brightness not responding. It used to decrease, but not increase. All of this running Gnome 3.
After days of fight what i did was download pf-kernel and configure it. I selected the "samsung_laptop" module as my common sense told me, and in case it was needed the Q10 Samsung or something like that module too.
I rebooted into the pf-kernel, with no luck, the same problem was still happening.
I decided to stop gdm and use startx to try some things.
First i modprobed the samsung_laptop module just in case, started X again, and it was the same.
And then i did modprobe -r samsung_laptop, restarted X... AND IT WORKS.
NOTE: The acpi_backlight=vendor is needed in the grub configuration to this to work.
Oddly, without the samsung_laptop module.
So i rebooted to try this again. Unloaded the module, did systemctl restart gdm, aand there it was working again.
So, it may be a problem with that module, or maybe its not needed after all, im not sure.
I'm kind of newbie in all of this, so if this is dumb or something im sorry but i think it may be helpful for somebody else in my situation.
By googling i only found scripts to make this work that i did not like.
Is neccesary that i place a bug report? Im not sure if that kernel module is made to fix this or if its for something else, so i dont know if the bug report makes sense.
Last edited by nlabrad (2012-12-27 18:07:52)

More history on what does what.
At first, i could only decrease the brightness 1 step, from the max to one below.
Then i put acpi_backlight=vendor in grub, and i could decrease the brightness to some value (which is not the real minimum), but could not increase it more than 2 steps over that minimum once decreased (like locked in the 2 lower values).
To manually change the brightness i echoed values to /sys/class/backlight/intel_backlight/brightness. The other one did not work (samsung...), but it wasn't what i wanted.
After changing kernel, unloading the kernel module samsung_laptop and restarting x it works.
Not sure if the kernel has something to do.

LCD brightness issue

I've installed archlinux on my laptop, everything works well except the brightness control.
The screen originally has 11 brightness levels, but when I either press Fn+F6/F7 key or use gnome-power-manager to adjust brightness, it always skips a level.
/proc/acpi/video/VGA/LCD/brightness
levels: 100 60 20 28 36 44 52 60 68 76 84 92 100
current: 100
I can only get level 20 36 52 68 84 and 100
The problem also exists in console mode.
I tried adding video module to blacklist, then brightness cannot be adjusted at all.
However, I never get this problem in openSUSE, all 11 levels are available.
Could anyone help me? Thanks!:|

http://forums.nvidia.com/index.php?show … t&p=386303
Hmmm...I found this on the nvidia forums:
I have a Samsung R700 laptop and my brightness stopped working after installing the restricted drivers. This is how I fixed it.
Press Ctrl-Alt-F1 to get a virtual console. Once you are in this console I think different video drivers are active so the following worked for me to adjust brightness.
Logged in and ran the following command:
echo -n 70 > /proc/acpi/video/NVID/LCD/brightness
then logged out and pressed Ctrl-Alt-F7 to go back to X
It's possible your brightness key on your laptop may work straight after you press ctrl-alt-f1 and you won't have to login and do the acpi stuff.
Also I have a startup script to set my brightness to a fixed value before X starts. It's not ideal but it's the only solution I could find that worked for me until the drivers are fixed!
Hope this helps.
Last edited by kclive18 (2008-07-08 11:19:25)

LCD Brightness is lowered when touching mouse or keyboard

Hi Guys,
hopefully, the newbie corner is the right place to post this, at least I am one, just switching from ubuntu to arch.
Essentially I have the problem marked as solved here: https://bbs.archlinux.org/viewtopic.php?id=127818
For me, however, it is not solved. I don't think it is related to laptop-mode, but I don't know. I am using my laptop on AC only. If I leave the laptop unattended for a while and then move the mouse or touch any button it lowers LCD brightness. The laptop buttons for brightness do work. I really don't know which program is doing this and neither why.
Since the system is pretty much unusable in this state, I did a workaround by taking away file privileges (chmod 444 /sys/class/backlight/nv_backlight/brightness).this has been overridden by the system after reboot, too.
I am using a fresh install with gnome.
Thank you very much in advance for any clues how to solve this.
Karsten
Last edited by karsten_m (2011-10-19 21:06:01)

Ok, the / of all the strange behaviour was gnome-power-manager.
Unfortunately I wasn't able to get to core of why it dims the screen, but the workaround is this: define the dimmed brightness as 100..
You can do this by running
dconf write /org/gnome/settings-daemon/plugins/power/idle-brightness 100
It does the trick.
If anyone's got a better idea - let it out...

T400 LCD brightness unstable

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