Comment 17 for bug 1628506

Finally, I had time to test it with linux 4.8.0-040800.201610022031 amd64 and with the 4.8.0-22 versions. In both cases the problem still exists. However, the content of the black rectangle has changed. It now includes the first line of the console frame buffer (in a slightly distorted way).

The bug #1611124 https://bugs.launchpad.net/ubuntu/+source/linux-firmware/+bug/1611124 might be related, as I get the same error with
W: Possible missing firmware /lib/firmware/i915/kbl_guc_ver9_14.bin for module i915
W: Possible missing firmware /lib/firmware/i915/bxt_guc_ver8_7.bin for module i915