[SOLVED] Fan / AIO Help!

[stanloona]

Hi all! First time builder here and i'm just really stuck with the whole fan and AIO placement situation:

My build will be along the lines of this: (I'm considering 12th gen CPU and switching to AMD GPU etc still but this is the general idea)
CPU: AMD Ryzen 7 5800X 3.8 GHz 8-Core Processor
CPU Cooler: Corsair iCUE H150i ELITE CAPELLIX 75 CFM Liquid CPU Cooler
Motherboard: MSI MAG X570 TOMAHAWK WIFI ATX AM4 Motherboard
Memory: Corsair Vengeance RGB Pro 32 GB (2 x 16 GB) DDR4-3600 CL18 Memory
Storage: Samsung 970 Evo Plus 1 TB M.2-2280 NVME Solid State Drive
Additional Storage (Still considering): Seagate Barracuda Compute 2 TB 3.5" 7200RPM Internal Hard Drive
GPU: GeForce RTX 3080
Case: Corsair iCUE 5000X RGB ATX Mid Tower Case
PSU: Corsair RMx (2021) 850 W 80+ Gold Certified Fully Modular ATX Power Supply

The question i have and where i'm confused on is fan / AIO placement? Would a top mounted AIO as exhaust and three standard case fans at the front as intake be enough? I'm just very confused and forums don't quite answer as i'd want some advice on my specific build. I want to keep corsair fans / AIO as i want a build feature to be RBG. With the case selected i've seen many people place fans on the side at the very front - is this neccessary etc?

Any help and advice would be brilliant thanks! Happy new year all!

 

[JohnBonhamsGhost]

Would a top mounted AIO as exhaust and three standard case fans at the front as intake be enough?

just try to be sure you have a positive air pressure inside of the case, a bit more intake than exhaust.

if using a 360mm AIO as exhaust out of the top and an additional 120mm rear exhaust,
i would shoot for ≥ 3x nice 140mm intakes.

 

[Paperdoc]

The ability to mount intake fans in the SIDE position near the front on that case is not really to ADD more fans. It's better regarded as an alternative location for fans that most people would mount in the FRONT panel. So plan as you have - three intake fans (Front panel as that case is supplied OR side), three rad fans as exhausts (top panel), one rear fan as exhaust. All of those will be 120mm size fans. The REAR fan is NOT included with the case, so you have to buy that separately, and ensure it is similar to your others in terms of fan type (3-pin Voltage Controlled or 4-pin PWM) and lighting type (IF you want lights in the rear fan). That many fans in total will provide lots of cooling so you won't likely need more. I note that, unfortunately, the spaces available for fans in the front and top panels are sufficient for three 120 mm fan per panel, but only TWO 140 mm fans per panel. So you could not boost your air flow much by making that change.

Looking at air flow capacity balance, I prefer to have slightly more intake capacity than exhaust. This is an old debate. My way is often called "positive pressure" because it means the case interior is at SLIGHTLY higher air pressure than the room outside, so any leakage of air at case cracks will blow air gently OUT of the case. Then all INTAKE should happen only through the dust FILTERS you must place at the intake fans (they are part of your case) to keep your case clean. VERY roughly, since all your fans are the same size, the COUNT of fans is a starting point. You would have three intakes and four exhausts. BUT the three intakes have their air flow capacity slightly reduced by the dust filters in front of them, and the three RAD FANS' air flow capacities are significantly reduced from having to force air out though narrow spaces between rad fins. (The Rad Fans are mainly for CPU cooling, but they do contribute to removal of warn air from inside the case.) So on air flow balance terms this arrangement should be close to what I personally prefer.

My only reservation here is the close proximity of the top front intake fan to the top front rad (exhaust) fan. They are very close together with little between them, and many people are concerned that this produces a "short circuit" of air that just makes a quick turn at the top front and zips out. For that reason SOME people would use a smaller rad cooling system of 240 mm length at the top, located close to the rear so there is no top front exhaust through a rad. On the other hand, that may well mean you have LESS capacity for heat removal from the CPU. You've chosen the larger 360 mm rad system, and Corsair clearly shows exactly that in photos (mostly to emphasize that this choice IS possible in that case), so I am inclined NOT to worry about that. IF you want to give this some thought, you MIGHT consider custom making a small air diversion baffle to mount at an angle down from the top front to direct air from the top front intake fan down into the lower part of the case before it circulates back up. Probably not necessary!

An alternative arrangement that many might prefer would address this "short circuit" of air. For this you would remove and re-locate all three of the front intake fans supplied with the case. Then mount your AIO cooler rad and its fans in the FRONT panel with the fans sucking air in through the rad. (Actually, you may be able to mount the fans on the OUTSIDE of the rad to suck air in though the front panel screen and blow it through the rad fins.) Because the rad fans' air flow capacity is less than that of unrestricted fans, this reduces total air intake a bit, but it ensures that the air coming though the rad is outside air slightly cooler than inside air. Then you mount in your top panel only TWO of the fans supplied with the case, in the middle and rear spots - NO exhaust fan at top front. This avoids the "short circuit" issue. Use the third supplied fan as your rear exhaust fan. The net result of this arrangement is slightly less total air flow through the case, but perhaps more efficient at in-case air circulation to yield very much the same amount of cooling to your major components. But it also creates the best possible cooling of your CPU since the rad has full air flow on all three fans AND that air is outside air. IF you wanted to, you might even consider adding one fan as an intake (need to mount a dust filter) into the front SIDE location at the BOTTOM to try to add more air flow near the intake area for your graphics card. Since the two bottom fans (front and side) both are intakes, there is no "short circuit" situation - just a bit of added flow turbulence in that area.

 

[Paperdoc]

Thanks for Best Solution. Enjoy your build!

 

[stanloona]

Thanks for Best Solution. Enjoy your build!

No problem! This explanation really helped put my mind at ease and has helped me understand the whole fan setup a lot better! Happy new year