Sorry, I don't know of any command line Linux overclocking utilities. It'd vary per chipset. Off the top of my head I don't know of a Linux-based clock generator for any chipset though it would help if you told us which motherboard.
A KVM switch? What does that have to do with overclocking?
Can you execute this?
$
cat /proc/cpuinfo | grep management
power management: ts fid vid ttp
fid=frequency identifier, vid=voltage identifier I believe, which means the adjustments are possible somehow.