Its BIOS. 1680x1050
x@x:~$ sudo update-alternatives --display desktop-grub
desktop-grub - auto mode
link currently points to /usr/share/images/desktop-base/lines-grub.png
/usr/share/images/desktop-base/joy-grub.png - priority 15
/usr/share/images/desktop-base/lines-grub-1920x1080.png - priority 15
/usr/share/images/desktop-base/lines-grub.png - priority 20
/usr/share/images/desktop-base/spacefun-grub-widescreen.png - priority 14
/usr/share/images/desktop-base/spacefun-grub.png - priority 15
Current 'best' version is '/usr/share/images/desktop-base/lines-grub.png'.
Thanks for looking into this,