Comment 84 for bug 1239186

(In reply to comment #40)
> Created attachment 94766 [details] [review]
> drm/i915: Increase WM memory latency values on SNB with high pixel clock
>
> This patch should make the driver automagically increase the latency values
> when encoutering a high resolution display. Please test and report back
> whether it works as intended.

Backported this patch on top of latest 3.13 based Ubuntu kernel tree, and indeed fixed the issue described by this bug (you can find more details at https://bugs.launchpad.net/xserver-xorg-video-intel/+bug/1239186).

Let me know if you need any further testing before sending the patch upstream.