Hi all! I was (and still am) happy with my Debian Lenny & fglrx on my HP Compaq NC8430 notebook with X1600 Mobility, but reading about the advances I decided to give the open power management a try. First I tried Ubuntu Lucid, with overclock.net's howto's I installed a new kernel and I was really impressed, now my fan spins almost regularly at 55% which is where fglrx (and Windows) make it too, without the recent power management advances it would be at 70% or sometimes even at 80%.
Power consumption was not as satisfactory, though. I managed to get Lucid at 27.4 W, whereas Lenny with fglrx is at 20.5 W, still far from Windows at 13-14 W. Powertop was constantly reporting something about sound modules that I tried to google but didn't find any other solution than blacklisting them, but it still didn't lower the power consumption.
Then I thought about why not trying Arch Linux, where no bloat is installed. I used to have Arch on my previous laptop, but due to overheating the X1600 I had stopped using it on NC8430. I downloaded the newest install image, and to my surprise the 2.6.33 kernel's KMS didn't work on my computer (the screen got all striped, like a loading screen of Sinclair Spectrum's tape programs making it unreadable, although I could see that the screen was functioning "behind the stripes"). So I had to disable KMS already at the install phase (and get the fan to 80%!). I updated to the new kernel on my hot computer, only to see that it didn't have power profiles (maybe it would have had dynamic PM but I didn't try it). So then another kernel from radeon repo and voilą, I had PM even without Xorg! However, power consumption is only marginally better than Lucid's at 25.9 W so there's still some work ahead, although I'm not sure whether it is with the GPU or other components, and I haven't undervolted the CPU yet which I always do with windows, there's a kernel version conflict with PHC that I try to resolve next.
If it is of any use for the developers, I post here some readings of the temperature sensors as a benchmark. I don't remember (or even know) what they are exactly besides the last one that is the fan percentage. The numbering has two ways, TZ0-TZ5 or T1-T6, but the order below is from smallest to largest (the last being the fan):
(When I tested Lenny the computer hadn't "warmed up" for these numbers to be comparable, but the power consumption was 20.5 W)
Temp sensor : T1 T2 T3 T4 T5 T6
Windows Vista: 50 44 43 39 20 55, power consumption 14 W
Ubuntu Lucid : 50 44 58 40 31 55, power consumption 27.4 W
Arch Linux : 50 45 56 40 29 55, power consumption 25.9 W
Time permitting, I am willing to run new tests to see how close to Windows Linux's PM can get.
So a big thank you and congratulations to the developers, you are doing really well!