Booting with ACPI enabled by default? (5.3)

[Ewald Jenisch]

Hi,

I've installed two system from scratch with 5.3 in the past few
days. One system by default comes up with ACPI enabled, the other with
ACPI disabled. 

Close watch has revealed that the boot-menu (the one that gives you
chose among ACPI yes/no, single-user-mode etc.) has it's default to
booting *with* ACPI on one system whereas it shows the default entry
with ACPI *disabled* on the other system.

What do I need to set/change so that a system comes up with ACPI
enabled by default (i.e. "with ACPI" being the default entry in the
boot menu)?

TIA for your help,
-ewald