I posted my /etc/pm/power.d/powersave.sh script that I created in response to the recommendations that powertop2 gave me. I'm using Arch linux but the settings aren't that much different for other distros.

Get powertop2 from AUR to verify that this script is working properly (check the Tunables before and after you run the script). They should all turn to "good". One other thing to note is that the script runs when the power state is toggled. Thus, if you are plugged in, the script restores things to the non-tuned state. So, to verify that the script is working, you should start powertop2 with your computer plugged in and then unplug it. It takes a few seconds for powertop2 to refresh the Tunables section.

This was written for my thinkpad T420, but it should work on nearly all current-gen thinkpads with the intel HD3000 card.

powersave.sh script is here: https://gist.github.com/92980c0a67e0b2d1bd43

powertop2 is here: https://aur.archlinux.org/packages.php?ID=48935

proof of the results is here (forgive the bad font fringing, i got the power going before making the fonts look good): http://i.imgur.com/rN09E.png

You should also edit your /boot/grub/menu.lst file to pass the special powersaving kernel flags at boot. The relevant stanza in mine looks like this:

  # (0) Arch Linux
  title  Arch Linux
  root   (hd0,0)
  kernel /vmlinuz-linux root=/dev/sda3 ro pcie_aspm=force i915.i915_enable_rc6=1
  initrd /initramfs-linux.img

Make sure that you re-run grub-install after changing this file. And, please, be careful. You could easily kill your system. To regenerate the grub file, do the following:

  #grub-install --no-floppy /dev/sda

*replace /dev/sda (above) with the root of your linux OS drive. This may be different for multi-boot machines.