Laptop display in 17.04 beta 2 is dim

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I have a Dell D830 and this newest beta is a marked improvement as far as I am concerned. 17.04 boots in a normal fashion and looks good. I don’t have to wait while the system gets its wind - its up and running within 30 seconds. However, my machine has a problem - the main display is dim - but a 2nd VGA monitor looks OK. My best guess is that the backlight is not turned on or is not fully activated. Is there anything I can do to fix this or to provide more information?

michael@D830:~$ inxi -ACDMNSG
System:    Host: D830 Kernel: 4.4.0-67-generic x86_64 (64 bit) Desktop: MATE 1.16.1  Distro: Ubuntu 16.04 xenial
Machine:   System: Dell (portable) product: Latitude D830
           Mobo: Dell model: 0HN341 Bios: Dell v: A13 date: 07/21/2008
CPU:       Dual core Intel Core2 Duo T7300 (-MCP-) cache: 4096 KB 
           clock speeds: max: 2001 MHz 1: 800 MHz 2: 1200 MHz
Graphics:  Card: Intel Mobile GM965/GL960 Integrated Graphics Controller (primary)
           Display Server: X.Org 1.18.4 drivers: intel (unloaded: fbdev,vesa)
           Resolution: [email protected], [email protected]
           GLX Renderer: Mesa DRI Intel 965GM GLX Version: 2.1 Mesa 12.0.6
Audio:     Card Intel 82801H (ICH8 Family) HD Audio Controller driver: snd_hda_intel
           Sound: Advanced Linux Sound Architecture v: k4.4.0-67-generic
Network:   Card-1: Broadcom NetXtreme BCM5755M Gigabit Ethernet PCI Express driver: tg3
           Card-2: Broadcom BCM4311 802.11a/b/g driver: b43-pci-bridge
Drives:    HDD Total Size: 2500.5GB (65.2% used) ID-1: /dev/sda model: WDC_WD5000BPVT size: 500.1GB
           ID-2: USB /dev/sdb model: My_Passport_0830 size: 2000.4GB
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Hi mdooley

This could help you out, at least worth a look :slight_smile:

https://wiki.ubuntu.com/Kernel/Debugging/Backlight#Testing_for_a_work_around

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I’ll check that out later this morning. Thanks v3xx.

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@anon42388993 Your link to the Kernel Debugging wiki was quite informative, thanks again. I went through many of the processes and then left it for awhile to haul some firewood up to the woodstove.

The link above got me started in the direction of a fix. I mounted the 17.04 beta2 partition in 16.04 and, after using MATE search for “dell_backlight”, did a comparison of the files in /var/lib/systemd/backlight/platform-dell-laptop:backlight:dell_backlight. The 16.04 partition showed “7” and the 17.04 partition showed “1”. I was able to open the 17.04 file as admin and changed it’s value to 7. Due to previous looking in /sys/class/backlight/, I knew that was the maximum value. I rebooted into 17.04 beta2 and all was well. Whew!

Edit: Not quite. In subsequent reboots, I noticed that I could only boot into 17.04 if I had an external monitor plugged in. Not good.

I looked into /var/systemd/backlight/ and saw a file in the 16.04 directory that was not present in 17.04, pci-0000:00:02.02.0:backlight:acpi_video0

Using administrative rights (gksudo caja) I copied the 16.04 file over to 17.04. I have since been able to boot into 17.04 beta2 successfully three times.

Another Edit: I reinstalled the beta using a cable connection this time resulting in a bright display. The file that I mentioned adding in my previous edit was not there. I also added a condition to my boot perameters - “video=SVIDEO-1:d” , just after quiet splash and before vt_handoff. This resulted in a faster and “no error” boot.

I found the boot tip on an Arch forum,

https://bbs.archlinux.org/viewtopic.php?id=218581&p=3

17.04 beta2 boots as fast or faster than 16.04 for me on this laptop. Now it’s solved.

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