Case fans

[hibeesmad]

Hey, I have the NZXT Lexa classic case however I feel the stock fans are too loud and plan to replace them (1 x 80mm) and (3 x 120mm). Does anyone know if the the stock fans are 3 pin or 4? Also, does anyone have a case fan install tutorial as I have never done this before, hope someone can help, thanks.

 

[dun]

Open the case and have a look to see if they are 3 or 4 pin
And fan install manual seems equally as confusing? Surely you will just repeat the procedure you used to remove the fans... but backwards?