H100i v2 3/4 pin fan installation, quick questions, need help

emberfq

Prominent
Nov 23, 2017
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510
So I'm a bit confused about the multitude of options I seem to have about where to plug in radiator fans as well as the water block cable, and how having 3 and 4 pin fans complicates this.

1. First, just a general question. The manual for the cooler is quite clear and straightforward. Water block goes in CPU_FAN on the board, radiator fans go in connectors attached to the water block. The fans that come with it are 4 in, the connectors are 4 pin also. Good times.
But on some Carey Holzman videos I've been watching he plugs radiator fans into the board directly from time to time, using CPU_FAN headers. And also he somtimes plugs the water block into a different W_PUMP header on the board. Now my board (Z370 AORUS Gaming 5) also sports several other headers, including the suspiciously named SYS_FAN_PUMP and HPWR_FAN_PUMP. I want to know what these are, even if they aren't what I should be using. Understanding why helps me in the future obviously. So what header has what purpose? Specifically CPU_FAN, CPU_OPT and those PUMP headers, and more importantly what is the difference between plugging the radiator fans into the provided cable hanging out of the block vs. directly into the board somewhere?

2. Now specific to my situation. 460X is a tiny case. Radiator up top is a no go. So now it goes at the front. This means, because there are already intake fans installed there, the ones that came with the radiator are obsolete. But those were 4 pins. The case fans that now double as radiator fans are 3 pins. Someone else told me that if I were to plug those into the 4 pin connectors on the water block they would spin at 100% all the time without any regulation in accordance with coolant temps. So that'd be kinda useless. Is this true? Again Carey Holzman has done that once and said it's no problem. Then again, that was with the old v1 version, the radiator fans of which were also 3 pins to begin with, so probably intended for that. My fans aren't. So what if I were to plug them into the board? And if so, where?
 
Solution
SYS_FAN_PUMP : regular powered pump
HPWR_FAN_PUMP : support for special high power pump up to 3 AMP
All fan pin headers were upgraded by Gigabyte to hybrid ones so they support PWM and DC mode for more compatibility with AIO pumps control.
3ym7VeQ.jpg

R0GG

Distinguished
SYS_FAN_PUMP : regular powered pump
HPWR_FAN_PUMP : support for special high power pump up to 3 AMP
All fan pin headers were upgraded by Gigabyte to hybrid ones so they support PWM and DC mode for more compatibility with AIO pumps control.
3ym7VeQ.jpg
 
Solution

emberfq

Prominent
Nov 23, 2017
8
0
510


But what about the fan headers on the water block? If I plug 3 pin into those will they also regulate their speed?
 

R0GG

Distinguished
3 pin fans will work fine as far as my personal experience with my builds where dep;ending on motherboard (some may require Bios adjustment) or water pump would switch automatically to DC mode if 3pin fan is attached to it while 4th pin is not populated, although pwm control seems to be more accurate and more rapidly adjusting than DC mode.