I use these fan splitters.
http://www.superbiiz.com/detail.php?p=CA-3F33F6K&c=fr&pid=562c1793d39375b826f936201eb9bdf07e96aba0dba15849d96c928c41b2545b&gclid=CMP5yqeI6b8CFQaOaQodTbAAWQ
Bitfenix Alchemy Multisleeved 60cm 3Pin Fan Male to 3x 3Pin Fan Female Adapter Cable (Black)