I have a T500 with: 01:00.0 VGA compatible controller: ATI Technologies Inc Mobility Radeon HD 3650 After X starts, when I switch to the console (alt+ctrl+F1), I do get the console but every few seconds the screen blanks and unblanks. This has started after upgrading to kernel 2.6.35, older kernels worked fine. I am running Gentoo Linux with: x11-drivers/xf86-video-ati 6.13.1 x11-libs/libdrm 2.4.21 media-libs/mesa 7.8.2 KMS is enabled.
Please attach your dmesg (after doing the problematic console switch) and xorg log. What was the last kernel that worked properly? Can you bisect what commit broke things for you?
Created attachment 37563 [details] dmesg after switching to console
Created attachment 37564 [details] Xorg.0.log after the console switch
The last working kernel was 2.6.34.2. I will try to bisect it over the weekend.
Created attachment 37569 [details] [review] Partial bisect log
I was able to do only a partial bisect and I attached the log hoping it will help. While bisecting I also noticed the following, when an external monitor is connected (through the DVI port of the docking station): In the good kernels when I switch to the console the external monitor keep displaying the last frame X was showing instead of showing the console. In the bad kernels, after I switch the external monitor displays the console (and it also flickers). Just to clarify - the flickering also happens if the laptop is undocked with no external monitor at all but I think the above is no coincidence and might help to solve the problem.
In my grub.conf file I had "video=DisplayPort-1:e" (this was in an attempt to use DP with the Intel IGP, also present on the T500). When I remove this option, the flickering is gone. I also saw that with the option enabled both the laptop LCD screen and the external monitor are set to 1024x768 when X starts, without it the resolution is set to 1680x1050 (the max of the LVDS). In either case, the DP is _not_ connected.
Mass closure: This bug has been untouched for more than six years, and is not obviously still valid. Please reopen this bug or file a new report if you continue to experience issues with current releases.
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