Ram won't generate heat like your processor will, make sure you're not blocking any vents on the machine, like a book laying too close to the laptop, or using it on a cushion on your lap, etc. The majority of modern laptops or PC's for that matter have variable speed fans installed, if it's getting too hot, the fan speeds up. Noise is a function of fan blade design and bearings used. so that really comes down to the manufacturer. My desktop has 6Gb of ram and I'm usually hovering around 40-45% RAM usage on windows seven with nothing open, 5-6 system bar items running. CPU usage idle sits at 1-2%