MacBook stuck at 1ghz?

I'm a sufferer of the RSD issue who sent my machine off months ago for repair. Since I haven't used the machine for much more than web browsing. With the recent joost invites I hoped on to check it out on the MacBook only to find it unusable. The interface would not respond and it was so slow I was scared about performance on the mac mini. To my surprise the mini ran fine as did the iMac. Further investigation shows the cpu clock on my MacBook is set to 1ghz. After a few hours of testing it never seems to move from 1ghz regardless of the load. Any one have any suggestions of bumping the clock speed or am I going to be stuck without a laptop for another x weeks while someone else has a go at hacking away the problems with this unit.