[critical] - ubtuntu restart problem

[Paco Raxim]

Ubuntu 18.04.1 LTS - gnome-shell 3.28.3 - using a laptop

on the base ubuntu system when I restart my computer, recently sometimes later half of my screen has got horizontal lines after boot (most of the time it happens from the login screen on), and the lines are flickering in a visible way. (like in a bad monitor)

I think, somehow the ubuntu corrupts itself before being restarted (the stop process seems to me too quick, but accoring to last command it's not crashing - i have seen crash, so i clearly differentiate).

It does not happen if I cleanly stop and start - but sometimes if i have restarted the computer ever, than on stop for a sec, the lines are visible.

Resetting the Hz (From 120 to 60 back and 60 to 120), on the settings panel, the problem disappears permanently, but only after resetting. (anyway it holds the ubuntu in a corrupt way permanently - even if i start / stop)
It happens I think in the last 1-2 month, never happened before, and i reported similar issues, but it has been ignored. (no there is the catch - a very bad ubuntu bug has been introduced)

It's a very bad issue, what I'm facing with. (HD5500 - AMD Radeon M260)

I thought it's coming from the obaif driver, but it's not the case. (the syslog does not show any meaningful error - so i think simply the ubuntu sets the whole thing with bad parameters and reload from it's corrupt cache)

It should not happen, even if the ubuntu crashes, or i just kill it with the power button! It's very-very critical bug.

(I tried to boot also from ubuntu usb, but never get the bios to the usb the first in the boot, that was the reason why i have restarted several times - it's very annoying to push F2/F8 whatever, and just for luck sake i get the bios)

I have a personal experience in an other computer 10 years ago, that the lines can be displayed on the monitor, if the monitor cannot deal with the HZ. So if the ubuntu corrupts itself, than it's suddenly try to set the HZ even further for example 140-150HZ, and the monitor is trying the best.

[Olivier Tilloy (osomon)]

Isn't that the same issue you reported in bug #1808646 ?

[Paco Raxim (raxim1)]

The thing is I have some driver mess up, and I had to clean some of them to find the root cause.

#1808646 can be closed as it's affecting the baseline of Ubuntu 18.04.1.

[Paco Raxim (raxim1)]

I have no time to reinstall the whole ubuntu right now, but I have cleanly removed the obaif, and the revert back was successful, although there is no error line that a Nvidia driver still persists on my ubuntu install.

I think even if I reinstall, the problem won't go away, as the problem seems to be quite clear.

Ubuntu is very stable on start/stop, but the graphics config has been corrupted while being restarted. (without any crash notice)

[Paco Raxim (raxim1)]

I have realized also, that it might be a hardware warm-up also.
(as if I try to start computer immediately after stop it happens - does not wait for a one-two sec)

I'm not quite sure, but I think the computer has been stopped. (blank screen and the ventilator has been stopped)

I might have used my computer on 60HZ - the lowest one, and that's why the problem has happened. (because now I'm using on 120HZ recently) - it might happen, that the problem won't happen if you use the actual lowest possible HZ, what the monitor can deal with, and don't change at all.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.