I use pm (pm-utils package, pm-suspend or pm-hibernate commands) to suspend and hibernate and this has options for the power down methods:
# kernel The built-in kernel suspend/resume support.
# Use this if nothing else is supported on your system.
# uswsusp If your system has support for the userspace
# suspend programs (s2ram/s2disk/s2both), then use this.
# tuxonice If your system has support for tuxonice, use this.
You can also specify suspend and resume modules in the config (/etc/pm/config.d/defaults). I do this for my wireless ath9k modules as otherwise my atheros wireless card doesn't power down.
You'll also need a resume=[swap partition] parameter in your grub's linux /boot/vmlinuz line if you use hibernate.
Of course they may have removed pm-utils in Chimaera, which would mean I'd have problems upgrading too.
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