adding fans behind the radiator

[jigspuge]

hello guys, I currently have the icue h150i elite capellix with 3 intake fans on the front.

 

I wanted to add 3 more intake fans at the back using this product https://www.amazon.com/Corsair-Hydraulic-Bearing-AirGuide-Technology/dp/B0BHTBQWM3/ref=sr_1_3?crid=HR3SG4ISVBWV&keywords=corsair+120mm+fan&qid=1708276469&s=electronics&sprefix=corsair+120mm+fan%2Celectronics%2C87&sr=1-3

its it okay or a good idea? what are the pros and cons on this? thank you!

[c-attack]

Typically referred to as "push+pull" fans, the pressure from the dual fans is additive.  This can lead to increased airflow in situations where there is considerable resistance from a thick and/or dense radiator or other types of resistance like case panels and dust filters.  The negatives are increased thickness of the combined fans (pushing 130mm in this instance) and noise.  Obviously 6 fans at speed X is going to be louder than 3.  

 

Most of the time I usually try to talk people out of doing this unless there is a specific reason or setup requirement for it.  It adds to the cost and doesn't fit well in a lot of cases.  However, if you have your radiator front mounted and that is the only intake pathway for the case, then you might benefit somewhat from getting a stronger airflow through the radiator.  Any decrease in coolant temp (and thus CPU temp) is going to be small.  Typically when the test 360mm radiators with a 300W load, you see 1-1.5C differences depending on fans speed.  So that's not the reason to do this.  What might benefit is your RAM, chipset, m.2 drives or anything on the other side of the radiator that isn't getting much airflow across it because the radiator takes half the air velocity of the front set of fans.  If you have a glass panel front with side air inlets, push-pull might also help overcome the additional resistance from that.  

 

The problem with the fans you linked is they will max out at 1300 rpm or about 1000 rpm less than the pair on the other side.  While you don't need or want to run them at 2400, it might be better to get a set that at least comes closer to mark.  This is especially true when it comes to managing the speed of 6 fans.  Most people will throw them all on a powered PWM repeater, which is effectively a SATA powered splitter.  All fans will receive the same PWM signal from the "lead fan".  In order to use it properly, you want the max RPM of all 6 to be similar.  The fans on the front of ML-Elite RGB (OEM).  They max out at 2400, unlike the retail ML-Elite RGB model with the polished frame and it's 2000 rpm max.  Corsair did not make a non-RGB of the ML-Elite this time around.  The prior ML-Pro black would be just fine and has the same 2400 rpm max, but it is out of production and very difficult to find now.  It likely would be more expensive than it's worth.  

 

So a couple options you can try:

1) Get a ML-Elite RGB 3 pack and do or do not hook up the RGB part.  In triple pack form it should be competitive on price compared to 3 of anything else.

2) AF-Elite black - Slightly different blade style and generally you would prefer to use similar blade types on either side, but it will work at with an 1850 rpm max is more suitable for radiator duty.  

3) Any other fan you can find with 7 generally flat blades like the ML-Elite and a speed of 1800 rpm or more.  

 

Since there isn't an exact match for speed with any of these, you may need to run a PWM repeater for just the back side and that would use 1 connection on the Commander Core.  I suspect you don't have a free one (3+2+1 rear), so that means either the top 2 need a splitter to share likely you just live with the differences in speed on the two sides of the radiator.  For the ML-Elite retail, that likely is going to be a small and acceptable difference at the medium speeds you are likely to use.