I have been meaning to update this bug report for a long time =
but I have been
having difficulty getting back to a stable system with the right combinatio=
n of
kernel, mesa & xorg-x11-drv-ati. Downgrading mesa makes no difference. I
suspect the problem is something in the kernel

This bug is severe for me, leaving my system almost unusuable. GPU lockup c=
an
happen anywhere from turning on the laptop to just before I get to gdm to l=
og
in. If I manage to log in the session might only last a few minutes. A long
lasting session is a rarity

A hard reboot is necessary. Often when I turn back on the system it just go=
es
straight away to a black screen. It doesn't even go the the Dell boot menu =
that
gives the bios options etc. The card would seem to be alive. Sometimes in t=
his
situation I get a beeping sound from the hardware.

However right now I seem to have hit a sweetspot with the following:
kernel-4.12.8-300.fc26
mesa-17.1.7-1.fc26
xorg-x11-drv-ati-7.9.0-1.fc26

I get long sessions lasting possibly hours without lockup. I still do have =
some
problems:

1: Even after a long session without a lockup if I shutdown the laptop norm=
ally
and try to boot it a few hours later it just goes straight away to a black
screen. It doesn't even go the the Dell boot menu that gives the bios optio=
ns
etc.=20
2:There are still the odd random lockup giving all the problems above

Should I change tack & report a bug relating to the kernel instead?