I noticed this happen when I was looking into another issue and plugged in the VGA output to an external display. It looks like it's a configuration mismatch in the i915 driver. DMesg logs will be provided shortly.
Ville recently submitted some fixes for VGA state readout on Haswell. Did you have these patches applied?
I don't believe so. The kernel version on the system is relatively old - 3.11.0-rc7 as I recall. I'm going to update the kernel today and see if it happens on the latest -nightly.
Is this still happening with recent kernels? if so can you attach the dmesg output?
We cannot go forward without more information. Ville did fix warnings around state readout for HSW and this is likely to be fixed. Please do re-open the bug if you reproduce it at a later point.
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