The BM1397 chips have a significant temperature coefficient, which means that they pull noticeably more power as they get warmer. Nobody at GekkoScience will be offended if a tuner or enthusiast upgrades the fan, as more airflow could mean reducing power consumption by 5-10% just from maintaining lower temperatures. These units take a standard 80mmx25mm 3/4-wire 12V case fan.
Speaking of this: is there any way to read out the chips' temperatures?
Or would we need to manually place a thermocouple and monitor it that way? I'm asking, because I replaced the stock fan and now I'm not sure whether it's getting too hot.