I have a HP6715S (AMD Turion twin core @2.0 Ghz, rs690/sb600 chipset, 3 gigs of ram) running slackware-13.37, and the power save functions are weird.

Hibernate hibernates - eventually, most of the time. The rest of the time it blanks the screen, disconnects input, writes nothing to disk and sits there. We're talking a 10-30 second wait usually, and the cpu fan going off seems implicated. It's just too often that the fan goes off and hibernate starts. If it's in limbo, the only thing is a long press on the power button, and ext recovery afterwards.

Suspend is more reliable, but always suspends twice. Wakeup is instantly suspended, and wakeup again wakes up :-(.

I have done my best to ensure only one thing controls the power saving activity, and that is acpid. Events start scripts which run either

sync: echo -n mem > /sys/power/state
or
sync: echo -n disk > /sys/power/state

XFCE's power manager has been neutered, and I usually use Fn & F3 or F6 combinations which register events with acpid.

I'd like an idea or two, particularly on the hibernate thing. Could it be kernel related (2.6.38.4?).

EDIT: Suspend sorted - non programmed behaviour from XFCE's power manager. I changed some inconsequential setting and it vanished.