GDM not showing up on boot

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Hi there,

I really need some advice, as I don't know further. After fedora 23 working fine on my Lenovo X230 for around 1 month, it started to throw errors on boot:

[    2.834738] [drm:intel_set_pch_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder A
[    2.834771] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun

(full dmesg)

Then, display output stops, but the system seems to be working hard bt is not responsive.

After some time I can switch on another TTY, login and startx manually.

The system runs then as expected.

From the errors above I researched and found others having similar issues with lower kernel versions. I had kernel 4.2.6 installed, so I saw no point in upgrading, but nonetheless i tried kernel 4.3.0 with no luck.

Any help or advice is appreciated, thank you!