You may also want to try i915.i915_enable_fbc=1 and i915.lvds_downclock=1

Both can, as always, lead to lockups but especially the frame buffer compression (fbc) is said to be noticeably powersaving.

But 5W so far is just wow!
Looks like I will definitely stay with thinkpads (the higher class) as even most modern notebooks use well more power than my by now almost ancient T60.
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Meanwhile fbc is already enabled. I'm not shure if it helps power savings. And occasionally I get glx crashes (2 or 3 times in the last 3-4 weeks) leading to X resets. But also not shure if it's related to fbc.

lvds_downclock seems to do nothing perceptible.

Lowest power readings have been 4.9 W yet
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How exactly do you measure power consumption?

What is your 'iddle'? Is Xorg running?

Here's my results:
Platform: Thinkpad x220 i7-2620m IPS SSD
HW settings: all radio turned off, lowest brightness
Software: No xorg, just bare system after reboot
Linux kys 3.1.0-6.dmz.1-liquorix-amd64
Kernel boot opts: i915.i915_enable_rc6=1 and NO pcie_aspm=force
Distro: Ubuntu (Kubuntu) oneiric 11.10

powerstats shows 5.6 Watts

And with full loaded Xorg, KDE with desktop effects and a dozen of widgets in tray, Thunderbird (with 5G of local imap cache), 3 Firefoxes with 10-20 tabs each, brightness 3 steps above the minimum, wifi on, bluetooth off, a Logitech mouse dongle (~0.4Watt) powerstats shows 7.5 - 9.0 Wats.

Before the liqourix kernel I've tried to load the default one (3.0.14) using all the options (pcie_aspm=force i915.i915_enable_rc6=1 i915.lvds_downclock=1 i915.i915_enable_fbc=1) in various ways. The lowest rate I got was 7.5 (no Xorg and no radio). So the liquorix kernel itself helps to reduce the rate by 2 Watts.


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I use the tp-smapi infrastructure (package tp-smapi-dkms) and there /sys/devices/platform/smapi/BAT0/power_no
Yes, my XFCE DE runs. Radios off, lowest brightness, speakers off. My quite minimalistic DE runs with as little as some 30 wakeups /s and my old samsung ssd is known for it's low power consumption ... that will be it, I guess.

kernel liq 3.1.0-6 with elevator=deadline i915.
i915_enable_rc6=1 i915.i915_enable_fbc=1 i915.semaphores=1 i915.lvds_downclock=1

I think your fully populated KDE running at ~ 8 W is pretty good and nothing to get grey hair about ... ;) My one needs 5.5 to 7.5 W atm with wifi, chrome and some conky stats, though (brightness 3 steps above min, too).
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