On 8/15/2012 6:47 PM, Daniel Vetter wrote: > On Wed, Aug 15, 2012 at 06:38:10PM -0400, Chun-Yu Shei wrote: >> Hi, >> >> I recently upgraded to a 27" monitor (2560x1440) from a 23" one >> (1920x1080), and had to switch to Windows because the new monitor is >> unusable in Linux. Today, about a month later, I decided to give >> Linux another try, since there have been several updates to the >> Intel graphics driver since then. >> >> Unfortunately, it seems that it's still unusable with >> xf86-video-intel 2.20.3 -- after a little while, the video signal to >> the 27" monitor completely stops, and it goes into power saving >> mode. I'm running dual monitors with the old 23", and that one >> continues running fine when this happens. This happens on my >> ThinkPad X220 (i5-2540M). The 27" is connected via DisplayPort, and >> the 23" via DVI. SNA is enabled, if it makes any difference (I >> haven't tried turning it off, but I probably should). This is the >> biggest problem I'm facing when it comes to Linux support. >> >> I also gave the new "TearFree" option a try, and while it does a >> great job of eliminating tearing, it makes the two monitors become >> mirrors of each other for some reason. If I take a screenshot with >> the GNOME tool, the screenshot comes out as expected (unmirrored), >> but the video output on the two monitors is mirrored in reality. >> Disabling "TearFree" fixes this. >> >> Also, when I'm using the ThinkPad's built-in display, it sometimes >> turns off for no apparent reason, although it's not too big of a >> deal since a suspend/resume cycle seems to fix things (and I haven't >> used 2.20.3 long enough to experience this yet). >> >> Any ideas/things I can do to help track these issues down? > > For the screen blanking issues, the kernel is the important part. Please > boot with drm.debug=0xe added to your kernel bootline and grab the full > dmesg. > -Daniel > OK, I finally got around to doing this... I just upgraded to the 3.5.3 kernel and xf86-video-intel 2.20.5 as well. Here's the initial dmesg upon bootup: http://pastebin.com/41F2AA0f And here's the dmesg right after the 27" goes blank: http://pastebin.com/3CTRETQ4 (not completely blank, though... there are a few lines at the very left & top edge of the display) A few seconds later, the display came back, and here's the dmesg right after that: http://pastebin.com/9mdfY5P1 Chun-Yu
