In another post I explained how to force a specific EDID on boot. It requires patching the initramfs to contain the EDID and then patching GRUB. On Fedora, this is slightly different. So I wanted to cover that here. Install Patched EDID Install the patched EDID (this example uses the pre-patched EDID attached here) and modify GRUB to use the new EDID. sudo mkdir -p /lib/firmware/edid cd /lib/firmware/edid sudo wget https://gist.
There are some monitors, in my case Dell U2413, that report having YCbCr support when plugged in over HDMI. My AMD Radeon RX 570 Series video card sees this YCbCr pixel format and then prefers that over the RGB pixel format. The result is that fonts, graphics and other visuals are pixelated and not smooth in Ubuntu. This actually is not just a Linux problem. With the same monitor hooked up over HDMI in macOS you get the same behavior.