I'm running Ubuntu 10.04 LTS (Lucid Lynx) on my Lenovo Thinkpad T60. I randomly get screen flickerings on my screen. Once it happens, it doesn't go away (unless I reboot my computer). I would describe the flickering as horizontal color lines appearing throughout the screen where the text is difficult to read everywhere.
I ran the following to see what video card is installed:
$ lspci | grep VGA
01:00.0 VGA compatible controller: ATI Technologies Inc Radeon Mobility X1400
My question is: what's wrong and how do I fix it?
Based on your description, sounds like Bug #541501 which is still open.
I have a similar problem on a Thinkpad T60 with ATI Radeon Mobility X1300. None of the workarounds suggested in the comments of the linked bug entry (
modeset=0
and/ornew_pll=0
parameters to theradeon
module, a newer mainline kernel) seem to completely make the problem go away for me – however, some of them seem to help a bit though.I'm now running Ubuntu 11.04 on my Thinkpad T60, and the screen flickering issue doesn't exist anymore.