Peace and quiet returns to my Mac Pro

It was all due to a clogged up heat sink in the ATI X1900 card that sits inside my Mac Pro – since the idle fan was not pulling in an airflow, it slowly wound up to full speed, until it was full-on all the time. The build-up of dust was quickly cleared by a blast of compressed air…but this brought about an idea – why don’t idle video cards reverse the fan for a few seconds, say once a day, in order to blow back any dust build-up? This way, the heat sink radiator would be kept clean and efficient.