hello i bought 5 3pin fans (in total i will have 6 fans )and they are 3 pin but on my motherborad it needs 4 pins (also i bought this http://www.amazon.co.uk/gp/product/B00EY9FYLS/ref=oh_details_o03_s00_i00?ie=UTF8&psc=1 by 3 as my motherboard has 3 system fan slots but they are 4 pin how can i fix this )