Rear fan needed with top 240mm AIO?

Gerr · April 12, 2019

I have a FD Define Mini C with a pair of Noctua 140mm front intakes fans and a single 120mm FD fan as exhaust with a air cooler on the CPU. I am looking to upgrade my CPU cooler to a 240mm AIO top mounted as exhaust and will use Noctua on it as well. Trying to keet the case as positive pressure. With 2 140mm fans as front intake and 2 120mm fans going through a radiator as top exhaust, will a single 120mm rear exhaust fan help with cooling at all and still maintain positive pressure?

WoodenMarker · April 12, 2019

It can help with cooling but how much it would help depends on your specs and how adequate your cooling already is.

Maintaining positive pressure is just a matter of running your intakes at higher rpm than your exhausts.

Turtle Rig · April 12, 2019

7 minutes ago, Gerr said:

I have a FD Define Mini C with a pair of Noctua 140mm front intakes fans and a single 120mm FD fan as exhaust with a air cooler on the CPU. I am looking to upgrade my CPU cooler to a 240mm AIO top mounted as exhaust and will use Noctua on it as well. Trying to keet the case as positive pressure. With 2 140mm fans as front intake and 2 120mm fans going through a radiator as top exhaust, will a single 120mm rear exhaust fan help with cooling at all and still maintain positive pressure?

I have 1 intake and 1 exhaust as per my signature. Temps are soo much better compared to my old old old case with the side panel open. With the AIO RAD you can make it so it takes air from outside and pushes it into the radiator. I tried this but the majore difdference is your going to get lots of dust and also since its pushing air into the case it will make your case hotter and your GPU warmer. You want to place the Rad up top then screw on the fans to push air out of the top.

Turtle Rig · April 12, 2019

Also 700rpm would suffice for your intake and exhaust. Push the hot air out of the radiator and out of the case up top, you will be pleased my friend. Also room temps matter but that's a story for another time.

Gerr · April 12, 2019

My CPU & GPU are both overclocked and I am hitting thermals more on my GPU. Can't OC any higher on air, but I know it can go higher on liquid. Plus hoping that the AIO pushes the heat directly out the top and should allow for a slightly cooler inside for more GPU headroom.

Turtle Rig · April 12, 2019

26 minutes ago, Gerr said:

My CPU & GPU are both overclocked and I am hitting thermals more on my GPU. Can't OC any higher on air, but I know it can go higher on liquid. Plus hoping that the AIO pushes the heat directly out the top and should allow for a slightly cooler inside for more GPU headroom.

Your GPU with 70 percent fan speed is very silent and will keep temps in the 60's c load. So long as you have 1 intake and one exhaust then the rad up top pushing air on the cpu out the top of the case.