Saving power on Intel/Linux has some interesting reading and references an interesting utility called powertop (which is available as a package in Ubuntu). It turns out there are some easy things to reduce the power used by a Linux server (or desktop or laptop, but I cared about the server) by a few watts here and there (or more, but I didn’t do before/after measurements). Even just upgrading to Ubuntu v.latest (8.04) probably saved me some power because the tickless kernel became standard.