The outlets in my apartment do not give a lot of power, and it's really easy to overload a circuit. I have a dual boot machine, and Windows XP runs OK on AC power despite this issue. XP will usually charge while on AC, sometimes it will neither charge nor drain the battery while on AC, but it runs reasonably well despite that.
Ubuntu doesn't handle the bad power nearly as well. It will rarely charge the battery, and often runs with a CPU load as high as 5 while on AC power, when the load would be around .1 on battery power. Dimming the screen doesn't seem to have any effect, and no particular program seems to cause the problem more than any other.
Does anyone have any insight into this, or tips to run Ubuntu in ultra low power mode? My machine is an Inspiron B130. I have tried a few different power supplies.