I have read that many people on this forum, including myself, have had very poor results with 2 fans on a 212. Its not going to make-or-break your machine, but it will either not do anything, or make it worse (as it did for me). If the "pull" fan on the 212 has to "push" air into the rear case fan, make sure the rear case fan spins much faster so there is no resistance. This wasnt the case for me... made it hard for my fans to push air out, resulting in a slight increase in heat.