Arch Linux

lightstream

Member

From: Britain

Registered: 2011-10-30

Posts: 69

Screen doesn't come back on after I reconnect the VGA cable

If I unplug the VGA cable on either of my two Arch boxes running XFCE, and then plug it back in again, the screen remains blank.

This happens even if I'm simply reconnecting to the same monitor e.g. after accidentally knocking the cable out.

I've never known this to happen on any DE other than XFCE, and I'm at a loss how to fix it. Right now I have to power-down the machine once the cable is in and restart. There must be a better way!

Incidentally, when I do power-down (by pressing the front panel power switch), the monitor comes back on as the system switches back to text mode, showing all the usual output during shutdown.

If anyone's got any ideas or suggestions where to start looking, I'd really appreciate it - my google-fu is failing me on this, I can't find anything related.

Trilby

Inspector Parrot

Registered: 2011-11-29

Posts: 30,456

Website

Re: Screen doesn't come back on after I reconnect the VGA cable

No need to reboot, just fix your display settings or use xrandr.

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"UNIX is simple and coherent" - Dennis Ritchie; "GNU's Not Unix" - Richard Stallman

Roken

Member

From: South Wales, UK

Registered: 2012-01-16

Posts: 1,340

Re: Screen doesn't come back on after I reconnect the VGA cable

You shouldn't really be connecting a VGA cable on a live system. Unlike USB and HDMI, VGA is not hot-pluggable and you could, potentially, short something.

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Linux user #545703

/ is the root of all problems.

lightstream

Member

From: Britain

Registered: 2011-10-30

Posts: 69

Re: Screen doesn't come back on after I reconnect the VGA cable

No need to reboot, just fix your display settings or use xrandr.

Do you mean there's some way to permanently fix the display settings? Or just when the cable is plugged back in, run xrandr? Problem is doing that without a screen!

VGA is not hot-pluggable and you could, potentially, short something.

This may be true, but on one system the cable is very loose and often gets knocked out. Of course it could be fixed permanently in place with the screws, but then any tripping over the cable results in worse catastrophe than just unplugging!

Also, I feel the voltages are very low and risk of damage is low. Hot swapping VGA cables is something I've done intentionally lots of times over the years. Thanks for the input though. XFCE is the first system I've encountered that won't just pick up the display automatically on plugging in.

Trilby

Inspector Parrot

Registered: 2011-11-29

Posts: 30,456

Website

Re: Screen doesn't come back on after I reconnect the VGA cable

Sorry, I thought you meant an second monitor.  If the primary monitor is not coming back on, something is definitely wrong.  You could set a keybinding to run and xrandr script so it would be easier to do "blind", but that would just be a workacround.

@Roken, do you have any sources/references for this danger?  Everyone I know "hot-swaps" vga all the time.  When people connect to a projector for a presentation, they never reboot, they just plug in and go, then unplug when the presentation is over.

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"UNIX is simple and coherent" - Dennis Ritchie; "GNU's Not Unix" - Richard Stallman

lightstream

Member

From: Britain

Registered: 2011-10-30

Posts: 69

Re: Screen doesn't come back on after I reconnect the VGA cable

something is definitely wrong

I'm glad to hear this, as it means there should be some way to fix the behaviour.

It's strange that it's happening on both my machines - both with quite different hardware (one is an Atom/Pentium CPU with Intel gfx, the other an Intel i5 with nVidia).

I wonder if I've missed some necessary package when installing XFCE on both machines. I'm 90% sure that when I was running compiz standalone previously, there were no similar problems switching the VGA cable between monitor and a large screen TV.

Last edited by lightstream (2015-11-12 00:08:54)

lightstream

Member

From: Britain

Registered: 2011-10-30

Posts: 69

Re: Screen doesn't come back on after I reconnect the VGA cable

You could set a keybinding to run and xrandr script so it would be easier to do "blind", but that would just be a workacround.

This seems to work, thanks. Like you say, just a workaround, but certainly better than rebooting or even killing the X server.

I'll try on the XFCE forums to see if anyone has got a better solution there.