Installing CORSAIR HX Series HX750 Power Supply Question

[ctpcbuild]

Just finished my first build and loving it so far. However, I am second guessing myself now. I installed a CORSAIR HX Series HX750 Power Supply in a Corsair Carbide Series 500R ATX Mid Tower Computer Case . I installed the psu fan face down but am now wondering if it should have been fan facing up. I think it is suppose to be face down so it will pull air into the case and force hot air out the back and top of the case. However, I believe if the fan is face down, it would pull air in, but only out the back of the power supply unit by the plug. So I don't understand how it would pull air into the case. Anyways, suggestions on installing the fan up or down? If you could provide rationale for your answer, it would be appreciated.

 

[ctpcbuild]

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