Question How to connect fan headers exactly in a push/pull configuration

Stocky1984

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I just ordered the Fractal Define 7 case with 2 more Noctua fans(NF-A14 industrial 2000rpm) to build this push/pull setup with my H115i Platinum watercooler. I have some questions about the correct connections of the fan headers. With my current case and setup (front rad push) I have these 2 same Noctua fans in front of the rad connected with a Y splitter to the CPU_FAN header because I didn't get them to work connecting them to the Corsair waterpump headers. There seems to be a PWM compatibility issue with these specfic Noctua fans(especially the 3000rpm version). Only the stock fans seems to work with it. The pump header is connected to CPU_OPT. The Define 7 has a fan hub and my original plan (like the manual describes) was to connect the 4 rad fans like this:

Naamloos.png


I would think having both push/pull fans on the same height on the same header(y-splitter) so therefore at the same rpm and would be the most benificial? Or doesn't really matter?
I also wonder if I need to use the Nexus fan hub that comes with the case at all for this because a lot of people on forums seem to stay away from fan hubs that comes with the case and just use MB headers only. But for that my MB has only 3 case fan headers and I'm not sure how I should set it up with 7 fans in total(all PWM: 4 push/pull, 2 on top, 1 on the rear) if it's not recommended to use the case fan hub. My GPU has 2 fan headers as well but these are not controllable through BIOS and AI Suite I guess. Thanks a lot in advance.
 
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alexbirdie

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CPU_Cooler fans with a y-splitter to CPU-FAN-header.
AIO-pump to CPU_OPT.

Case fans to the chassis-fan-header( there are 3 on the motherboard). EXT_FAN does have 5 pins, no idea, what it is for.

For the case-fans you can use y-splitter,too.

Every header provides 1 A and fans usually need only 0.15 A. That means, up to 3 fans can be connected to fan-header with splitter absolutly safe.
 
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Stocky1984

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Thanks a lot! I'll try the case fan hub first like in the picture, if that doesn't work I'll try your plan. Not sure if it's recommended to have all 4 radiator push/pull fans on the same CPU_FAN header tho. Need to get a 4 way splitter for this anyway.
 
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Stocky1984

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Well I tried the case fan hub(like in the picture above) and it didn't work so I put 2 front fans (on the top part of my radiator which line up with my CPU) with Y splitter on the CPU_FAN header and the other 2 front fans (on the bottom part of the radiator) with Y splitter on a CHA_Fan header, AIO pump to CPU_OPT. I ordered another 2 way PWM splitter to have the 2 top fans on another CHA_FAN header, I only use the top fan at the back for now. Rear fan connected to the 3th and last CHA_Fan header.

I had a front rad push configuration before and now with this push/pull configuration I'm down at least 5 degrees on CPU temps.

20200629-231512.jpg


This probably doesn't do much of a difference but I put the 2 stock fans which came with the case on the bottom of the case to give the GPU more fresh cool air. These 2 are connected to the 2 GPU fan headers which I control through ASUS GPU Tweak. I can't control those through MSI Afterburner so I switched to ASUS GPU tweak for general overclocking.

20200629-231422.jpg