Since my bug has been marked as a dupe of this I'll copy some other info from there:
PC is an eMachines 370. Fan worked under previous versions of ubuntu, but no longer comes on under edgy. As well as this acpi reports bogus temperatures: ~$ cat /proc/acpi/thermal_zone/THRM/temperature temperature: -267 C ~$ acpi -t Thermal 1: passive , 4294967040.0 degrees C bug 24308 and bug 54554 also seem similar -- CPU fans won't start https://launchpad.net/bugs/70739 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs