[QUOTE=ChristineBCW;2652668]The 4th pin is definitely the PWM-controls. A 3-pin fan will run constantly at one speed while a 4-pin PWM fan can vary its RPMs based on BIOS settings, temperatures, etc.
Kind of a letdown, huh? I was first cackling with the “anything could happen!” warning, thinking maybe your computer would be turned into a helo-powered box, flying around the room because of an errant fan at 30,000rpm, maybe chasing you 'round and 'round.
Boy - I never get to have any fun![/QUOTE]
Well rather than provide you with tales of my liftoff box, and to make sure that I had the proper LGA 1155 brackets, as well as to avoid a long train trip I ended up buying the AT unit. Should be here tomorrow in all its shiny, coppery goodness. One thing I like already is that it doesn’t have those pain in the ass push pins.