Created attachment 123560 [details] dmesg with drm.debug=0x1e Hardware: Dell XPS 15 9510 http://www.dell.com/support/home/au/en/aubsd1/product-support/servicetag/F1BFJ72/configuration?s=DHS AOC U3477PQU Monitor http://aoc-europe.com/en/products/u3477pqu Software: Debian Jessie (Testing), + linux-image-4.5.0-2-amd64_4.5.2-1 Problem ======= All sorts of horrible behaviour when a AOC U3477PQU is plugged into the laptop's HDMI port ranging from both Laptop LCD and Monitor flickering for a while (sometimes seconds, but once literally 8 hours) before working to machine hangs (as in keyboard caps lock indicator doesn't change when you press the caps lock key) before X attempts to start. There are lots of backtraces in the attached dmesg which seem related.
Created attachment 123561 [details] Xorg.log
Duplicate of bug 89055 ?
Thanks for that pointer. It is exactly the issue mentioned in https://bugs.freedesktop.org/show_bug.cgi?id=89055#c31 in bug 89055. But I see https://bugs.freedesktop.org/show_bug.cgi?id=89055#c40 says the issue is fixed in 4.6. However, the backtrace bug 89055 remains in 4.6, so no, it's not related. Since it's fixed in 4.6 I'm closing the bug.
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