Do i need optional fans or stock will do just fine?

Solution
Front: 120mm black fan x 1
Rear: 120/90/80mm fan x 1 (optional)
Bottom: 120mm fan x 1 (optional)
Side: 120mm fan x 1 (optional)

You should get 2 more it only comes with 1 intake as shown above , 1 for rear exhaust and 1 for top exhaust.

bboiprfsr

Honorable
Dec 23, 2013
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You don't necessarily need a side fan unless you want your graphics card to be cooler by a couple degrees C at load temperatures at O.c.. Blackbird is right, you definitely NEED 2 additional exhaust fans, at the back rear and at the top. this will lower your idle temps by 1-3C and your load temps by 4-6C minimum (depends on each person really).