keeping the radiator fans as 'intake' will be better for cooling the coolant, but will introduce more hot air inside the cabinet.
No. Not necessarily. Unless you're stuffing it in some closed furniture or something like that.
Where did you put the radiator? on top of the 200m fan grill of the HAF 912?
Assuming we're talking about the system on the OP's signature, its shouldn't be a problem in the first place, though investing so much on a cooling for a non k version cpu where most likely you're not overclocking manually in the first place doesn't really sound right at all. Its your wish, though. Putting more fans on the case would probably make things redundant or/and worse.
It should be noted that not all radiators benefit from push pull (also applies for CPU coolers) and not from better fans. When Seidon XL was tested even with Noctua NF12 fans, it didn't make any difference, except that the annoying sound with max speed on CM fans didn't exist.
Like that if you see when cases which allows you to install 240mm sideways take air in anyways, same applies for top panel fans and even in cases like HAF XB. Its not a problem.
Take out the side panel fan and use it as exhaust on the rear.
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