Pretty easy actually. See how the metal mesh is held in place by the folded bits? Just fold them back and slightly separate the metal mesh from the top panel. Then you just slide the filter out.

Alternatively, you can just try and tug the filter out. It's not securely fixed to the top panel.

to be honest, adding more fans to the casing doesn't really affect the temperature in the casing much, in my haf 912, my rear fan already rosak for probably a few weeks, now no time to change, but everyday, i check the temperature of the cpu and gc, it still the same as b4 when the fan is working well..(im using cm xtra flow fan, just used like mayb 3 months then rosak..wtf  )

same goes to my old cm690, especially the fan in front, its more like a decoration thing for me, even add or no add, the harddisk temperature is not even affected, so if you think that adding more fan to the casing will really affect ur temperature much, try to do some experiment

Cooler Master 692 Advanced Watercooled (XSPC RASA RX240 Kit)

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