Arch Linux

burt1iband

Member

Registered: 2016-03-14

Posts: 2

vbetool stopped working to turn off monitor on Dell e4300

Until recently I could use vbetool to turn off the monitor on my laptop, but all vbetools commands I've tried to run now  give an illegal instruction error.
The machine in question has  i915 Intel Graphics. I'm a blind screenreader user, and the extra battery life gained by blacking the monior is significant, and it is also helpful to not bother my sleeping wife with laptop glare by the bed...lol
Any ideas on how I can turn off my monitor from the console other than vbetool? I run a custom fluxbox bsed GUI, but often do not start it doing my work in the CLI environment, so an X only app would be better than nothing, but I'd prefer to work directly on a lower level if practical.
sudo vbetool dpms off sill works on Ubuntu with the 3.19 kernel. Not sure exactly when it stopped working on the arch box which is updated pretty much daily, but the illegal instruction error is pretty recent.
Thanks

Last edited by burt1iband (2016-03-14 07:11:25)

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 20,654

Re: vbetool stopped working to turn off monitor on Dell e4300

This is merely a guess, but have you installed and configured microcode updates for your processor?  It could be the cause of the illegal instruction.
https://wiki.archlinux.org/index.php/Microcode

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burt1iband

Member

Registered: 2016-03-14

Posts: 2

Re: vbetool stopped working to turn off monitor on Dell e4300

Well, I did actually have to remake my boot partition a month or two ago due to a stupid error on my part, and I did forget to add the intel-ucode prepends to my syslinux.cfg file when I did this. Sadly doing the edit seems to have had no effect. I noticed a confusion/error in waiting in the wiki. It says to sopy the dots as they are, but puts append ... below the INITRD line...lol/will see if that is protected or if I can improve the wording after I get home from a bit of work.
No updates appear in dmesg output, will double check later to make sure there are not any I'm not getting.
Bottom line, I still need to figure out a way to turn my laptop screen off and on.
Thanks/at leastfix those boot loader  configuration lines. More ideas are welcomed of course!