[lug] screen frequently blacks out on recent update...

[Davide Del Vento]

For the coroners among us...

Changing the graphic card made the problem occur only on one screen (first
occasionally, then and more frequently). It turned out, the power supply of
that one screen was fried. Apparently, that happens when some electrolytic
capacitors blow up (they bulge) and the screen goes blank, but the power
button and the LED indicating that the monitor is up both work, confusing
people like me who think "the LED is on, so power supply must work ok".
It's a common problem, especially with inexpensive monitors. I could have
replaced the affected capacitors for about $20, putting high quality parts
instead of the crap they used initially (almost half of the price was in
shipping....) but decided that a very old, low-quality display was not
worth the hassle for me (especially since I had a good monitor laying
around for the kids' raspberry pi which had been unused for 6+ months: so I
took that)

On Tue, Jan 22, 2019 at 4:27 PM Bear Giles <bgiles at coyotesong.com> wrote:

> It didn't seem to help...
>
> ... but possibly related, possibly not, on the Ubuntu desktop I tried to
> run an X app remotely (with ssh -Y) and managed to lock up the system. When
> it came back GDM did not - I just stare at an off-purple screen. It's still
> on that screen even if I go walk my dog.
>
> I did dpkg-reconfigure gdm3 with no luck.
>
> Fortunately Kubuntu still works. It's still extremely frustrating.
>
> On Tue, Jan 22, 2019 at 10:56 AM Bear Giles <bgiles at coyotesong.com> wrote:
>
>> Thanks, I'll try that.
>>
>> These are both Dell 4k monitors and both have been working fine. The
>> desktop can use both monitors but it can also be configured to use one
>> while the laptop uses the HDMI port on the second monitor. I haven't had
>> problems with this configuration in the past.
>>
>> On Tue, Jan 22, 2019 at 10:51 AM Davide Del Vento <
>> davide.del.vento at gmail.com> wrote:
>>
>>> I have this happening occasionally to me. Changing the cables did not
>>> fix it. Power supplies in the monitor seemed unlikely, since it randomly
>>> affected either one of two monitors. Bad graphic card could be, however I
>>> inadvertently found the following workaround which stops the problem for
>>> the day and prevented me from worrying more about it (the machine will need
>>> to be replaced in several months anyway, so not worth my time once I've
>>> found this): go in pure-text mode (CTRL-ALT-F1), stay there for a few
>>> seconds, go back to graphic mode (ALT-F7). Without this workaround, the
>>> problem will continue so much to make the machine close to useless.
>>>
>>> Hope this helps.
>>> Davide
>>>
>>>
>>> On Tue, Jan 22, 2019 at 8:39 AM D. Stimits <stimits at comcast.net> wrote:
>>>
>>>> On January 22, 2019 at 5:15 AM Bear Giles <bgiles at coyotesong.com>
>>>> wrote:
>>>>
>>>> Has anyone else seen their screen frequently blank out for 1-2 seconds
>>>> after a recent update? This is happening on both an Ubuntu 18.10 and CentOS
>>>> system. I don't think it's a hardware issue since it's two different
>>>> systems, two different monitors, and both have worked fine until the last
>>>> few days.
>>>>
>>>> I've had this occur when the power supply in the monitor was going bad.
>>>> I've also had this occur when the cables needed reseating. I also replaced
>>>> what I believe was a bad video card once for this (the problem went away
>>>> for a while). I also did not believe it was the monitor because it affected
>>>> both monitors, but if you have more than one, and hot plug detects one go
>>>> out and back in, they *both* blink as it reconfigures. More often it
>>>> has been the power supply going out (I've replaced power supplies within a
>>>> couple of different monitors...apparently this is more common than it might
>>>> appear). Perhaps the update was just coincidental.
>>>>
>>>>
>>>> Both are running Gnome.
>>>>
>>>> (BTW I never managed to fix Gnome under 18.04. I eventually updated to
>>>> 18.10 and it now works... but oddly I still get the Kubuntu logo when I'm
>>>> prompted for the hardware decryption password.)
>>>>
>>>> Bear
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>>>>
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>>>
>>> _______________________________________________
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>>
>> _______________________________________________
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