I've forwarded this bug upstream to https://bugs.freedesktop.org/show_bug.cgi?id=27278 and subscribed you to it. Please follow up with them in case they need further information or wish you to test something.
The timing of starting to see this as of a few weeks ago is interesting in that roughly that's when we moved from the .32 to the .33 drm (the 2.6.32-16.25 kernel). Now, if drm was at fault, I would suspect that turning kms off would work around the issue, so it's odd it only delayed when it appeared. Hopefully upstream will give us some good feedback on this. Meanwhile, another thing to just check would be to boot to an older kernel - get into grub and select a kernel of version 2.6.32-15 or earlier. If my guess is right, the issue should go away at that point, and it will pinpoint the problem to a regression in the .33 drm. On the other hand, if it still shows the bad behavior, I would start wondering if there is a hardware issue maybe? I've seen this on my own hardware when there was magnetic interference near the monitor or the cable, or when using an extra long cable. Electric interference (such as a non-grounded outlet on the same circuit as an appliance or tv) could cause it. From how thorough your reporting has been I assume you've ruled out something like this already, but thought it would be worth asking. ** Bug watch added: freedesktop.org Bugzilla #27278 https://bugs.freedesktop.org/show_bug.cgi?id=27278 -- [RV515] [LENOVO T60] external screen display shows "shivering", horizontal refresh offset https://bugs.launchpad.net/bugs/541501 You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-ati in ubuntu. _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp
