Running cpu-z will tell you what its running at. Depending on the processor and if its an Intel or AMD and if you have their software enabled in bios then it could run at a slower speed until its needed and then the software will raise it back up to stock. The software I'm talking about is Intel's speedstep software and AMD's cool N' quiet software. This software is designed to keep the processor cool when really not needed but will speed it back up to full speed when needed.