HDMI

I had an issue with my server where it would stop sending an HDMI output signal when the display was switched off and back on. (Result: The display said "no signal")

Kernel Boot Option

Since I am not running X on this machine I had to resolve it through the kernel nomodeset boot option: In /etc/default/grub I added the option to show

GRUB_CMDLINE_LINUX="nomodeset i915.modeset=0 "

The i915 option was for the intel graphics card. For Nvidia graphics card you need to add nouveau.modeset=0. For Nvidia Optimus dual-graphics system, you need all three (i.e. "nomodeset i915.modeset=0 nouveau.modeset=0").

Also see the KMS Arch Wiki page

Console Fonts

After this change, my console fonts were messed up. The solution was to change the console-setup config in /etc/default/console-setup. I changed

FONTFACE="Fixed"

into

FONTFACE="VGA"

and all was good.