.Markku Reunanen.

Intel HD Graphics, low resolution and stuck in mirrored mode

August 7th, 2019

This issue hit me today, and as I didn’t find any proper answer by Googling, it might be useful to share the possible solution here. After swapping an SSD from a busted laptop to a working one, Linux Mint happily detected everything, except that the graphics mode was stuck at 1024×768 resolution with no possibility to change it. The internal and external screen showed the same content instead of an extended desktop. First I thought it was somehow Mac-specific as the two machines were MBPs, but no. The advice found online tells you to create new resolutions with cvt. No.

Did you swap the drive from a machine with a discrete graphics chip? Did you use another machine to do the install? Or did the installer maybe just f*ck up? A-ha! It turns out that the kernel boot parameter “nomodeset” is the culprit, as it is used with discrete chips’ (proprietary) drivers only. On the Intel HD it shouldn’t be there, as the driver relies on kernel graphics mode setting. Go and check out /etc/default/grub and find a line saying:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset"

Remove the keyword – must have root access for that – and then run update-grub (again as root). After this reboot the machine so that the new kernel parameters take effect. Worked for me, and now my HD 3000 is happily displaying 1440p on the external screen.

Filed under: laitteet,linux,mac