Might mention ACPI state options in dmesg early on during boot, or you could probably poke at some ACPI diagnostics/options to see the capabilities. I think `c

Might mention ACPI state options in dmesg early on during boot, or you could probably poke at some ACPI diagnostics/options to see the capabilities. I think `cat /sys/power/mem_sleep` should tell you the desired modes; the active mode is selected and iirc changing one is done by writing the name of an option into the file. There are some related files next to `mem_sleep` in `/sys/power/`.