multiplier question

[Sumoquirkey]

is it normal for cpuz and core temps to tell me my multiplier is going from x23 down to x12 and back up ,continuosly ...i have a ocuk package, asus p6x58d-e mb and bloomfield i7 950 .,im not an overclocker by any means and havent dabled with any settings,but since this hot weather has been upon us i ve had a few times when the pc has locked up ,frozen and had to be reset, so i thought things might be getting a tad hot,so cleaned out filters,they were clogged !! another question i have corsair hydro 50 cpu cooler,ive never noticed or heared the fans running on it ,this normal ? do fans kick in when cpu is under heavy load? temps in bios are 47c ..sorry for nub questions but if someone could put my mind at rest id apreciate it
cheers in advance

 

[iostream]

To answer your first question: as far as I am aware, that is "speedstep" in action, it adjusts your CPU frequency on the fly depending on load, hence why you'll be seeing the change in your multipliers. I believe the idea is to conserve power and therefore also to reduce heat. No point running at full tilt if you are only playing minesweeper