there is no such thing as 44ghz, i think you meant 4.4ghz, because if it was at 44 your computer would explode. Now that I think you mean 4.4 and 1.6ghz, I think its just because of what your computer needs at the time. If you're just browsing it might go down. If you are gaming hardcore, then it might go up. Computers do this to be efficient, and only use the energy when they need it.