Public bug reported:
As the summary says. This is 100% repeatable and there's been a fair
amount of traffic about it on various lists.
The current concensus is that the root cause is down to to powersave
mode tweaks in all GPU modules
To repeat:
install multiple nvidia GPUs in a desktop system (or a multi-gpu card
such as nvidia Quadro CVS440)
Boot up Trusty beta versions (or 2.13 kernel).
try configuring displays using standard tools based on xrandr
This worked fine in Saucy (crosscheck: boot off 13.10 64bit DVD)
Apparently this is fixed in the 2.14 kernels.
It can be worked around by manually configuring the devices in xorg.conf
and enabling Xinerama, BUT - this results in massive slowdown and as
this disables xrandr a number of important apps (such as vlc) will
refuse to run.
This is a major regression and needs to be treated as such.
** Affects: linux (Ubuntu)
Importance: Undecided
Status: New
** Tags: gpu
** Description changed:
As the summary says. This is 100% repeatable and there's been a fair
amount of traffic about it on various lists.
The current concensus is that the root cause is down to to powersave
mode tweaks in all GPU modules
To repeat:
install multiple nvidia GPUs in a desktop system (or a multi-gpu card
such as nvidia Quadro CVS440)
Boot up Trusty beta versions (or 2.13 kernel).
try configuring displays using standard tools based on xrandr
This worked fine in Saucy (crosscheck: boot off 13.10 64bit DVD)
Apparently this is fixed in the 2.14 kernels.
It can be worked around by manually configuring the devices in xorg.conf
and enabling Xinerama, BUT - this results in massive slowdown and as
this disables xrandr a number of important apps (such as vlc) will
refuse to run.
+
+ This is a major regression and needs to be treated as such.
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1303150
Title:
2.13 kernels (ALL) : Multihead multi-gpu broken for at least Nvidia
GPUs
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1303150/+subscriptions
--
ubuntu-bugs mailing list
ubuntu-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
