Laptop Processor Core Clock Speed Curiosity

[peeeej]

So I've noticed this since I got into computer components and what not. My laptop has a processor Intel i3 3210m and I looked it up in the page of intel and it says that processor base frequency is 2.5ghz but when I open CPU-Z, the clock core speed is at 1.2Ghz. I tried to use prime95 to stress test my laptop to see if the clock speed will increase to 2.5ghz but it was stable at 1.197Ghz. Will someone please explain this to me? Thank you very much in advance 

[DunePilot]

Perhaps some kind of thermal throttle issue. Laptops are usually very limited by heat, cooling is absolutely terrible on most. Try something easier and more real world scenario like Cinebench. Also under control panel put the power options to performance when you are testing, I'd put it back on balanced when you are done.