Just to be certain, the return of this should be legacy boot.
[ -d /sys/firmware/efi ] && echo "EFI boot on HDD" || echo "Legacy boot on
HDD"
It sounds like the laptop wants to boot from an EFI partition but you don't
have one, you are using the MBR. IIRC there should be an option to install
EFI in the advanced Trisquel install. Failing that, you should have a GUID
partition table with a fat32 partition (~500mb) at the beginning, sda1, with
boot flag. Then you install grub-efi which will install to the sda1 partition
(/boot/efi) and not the MBR. Then you should be able to boot normally.
Unfortunately this will mean repartitioning, so probably a fresh install.
Sorry to hear it didn't auto detect the EFI setting on install. I have heard
it can happen where a BIOS is given EFI booting. Your laptop definitely has a
BIOS, I looked it up. Also, refind is a useful tool.
If you need me to clarify anything, just ask.
