Thanks. The modification to “batocera-boot.conf” you mentioned does work, although my GPU is Intel 915GM, not 965. On Batocera 27, which did not work on my laptop, after the modification, I can operate the Batocera UI. As to the speed, I have not measured.
I also tried to set “intel-i9i5-driver = true”, hoping it may be useful. In the end, it seems making no sense to Batocera 27 and I only see black screen.