It seems that only the acpi-cpufreq module is included in the x86-64 version of the kernel (haven't tried the normal 32-bit version) the p4-clockmod module is missing. It this on purpose? My system (dual EM64T Xeon) doesn't like the acpi module. I usually run my system with the ondemand governor to throttle it down when I am not really using it. Otherwise FC4t2 64-bit runs great. Jurgen