Q:

ubuntu server 16.04 get stuck on startup, show i915 **error** pch transcoder a fifo underrun

My ubuntu server 16.04 suddenly get stuck on startup, and I cannot enter into the system, the error message is:
[drm:intel_pch_fifo_underrun_irq_handler [i915]] **Error** PCH transconder A FIF0 underrun

I find a solved answer at this, but I still don't know how to solve this problem.
Should I reinstall the system, or do sth else the fix the problem?

A:

I meet with this problem because I change the grub setting of my ubuntu.
At the beginning, I want to disable blank screensaver, so I refer to the solved answer of this. After I finish sudo update-grub and reboot my computer at the next morning, I meet with this error and cannot enter the system. 
So, to solve this problem for me, I just revoke what I do about the grub and sudo update-grub and reboot. 

