Hi this maybe normal - or not..? Have a 27" iMac maxed out (bar the 8gb ram). During anything intensive, eg converting video files via handbrake or converting multiple video files from WMV to mp4, the fan spins up fairly loudly for a short period and spins down again. Not overly bothered by it, but wondered if it could give me problems down the line, is it worth getting it looked at? Alternatively is there anything I can do to resolve it myself? thanks!