When Idle'ing intel cpu's go into a halt state which lowers the processing speed. Try doing somethign that will strain the cpu, and the freq will go back up to normal levels. you can turn it off by giong into bios and turing enchanced halt state off.
yea your right, got scared for a sec because I was doing some test overclocking and then set it back to defualt and thought I fucked the cpu or something.