Ubuntu on the Dell 700m - Hacking Journal [2006/02/21]
Have not had much time for any in depth hacking but I did get to get my Dell 700m running good again. It is running Ubuntu and has been having some issues with lockups recently. It would randomly lock up if it was running of the battery for some reason.
I spent some time testing it (turning acpi and stuff on/off) and finally traced the problem back to the powernod deamon. This is the daemon that will scale p the processor under load and scale it back down. I found some people on the Ubuntu Forum have had issue with this before so it was nothing new.
What I did that fixed it was first install the i686 version of the latest kernel and then change the settings for powernowd to use the “SINE” mode of operation instead of the default “AGGRESSIVE”.
I tested it a few time and each time the system stayed up until the battery ran out of juice (~4hrs). To change this in Ubuntu, you need to create a file /etc/default/powernowd and set your OPTIONS to be what you want. For the “SINE” mode it should look like this:
OPTIONS = "-m 0"
UPDATE: I have been testing my laptop and found the setting at -m 2 or -m 3 are also causing lockups when on battery power.
Eric Davis
