Require help with proper fan hub management

ioverclockers

ioverclockers

ioverclockers

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Hi !
I'm about to do my first build and as I intend to do some real overclocking, I made sure I got enough airflow in my case. I have 7 BeQuiet! Case Fan SilentWings 3 120mm PWM HighSpeed - BL070 fans and the two 140 mm fans of my CPU cooler : ZALMAN CNPS20X. My motherboard is the ASUS ROG Crosshair VIII Hero (wifi).

This is the breakdown of the Mobo for all-fan related stuff :
1 x CPU Fan connector(s)
1 x CPU OPT Fan connector(s)
3 x Chassis Fan connector(s)
1 x AIO_PUMP connector
1 x H_AMP fan connector
1 x W_PUMP+ connector

Now I know plugging in that many fans is a tricky one. Is it correct I shouldn't go higher than 1 A ?
I guess I need some sort of PWM fan hub (or more than one). Also wanted to add that I don't need anything RGB related hubs if that can make a difference.
What would be the correct setup and where do I have to plug the hub into ?
Thanks for your help...
 
Thx for the reply, which made me aware of a typo in my first post. I actually meant where do I have to plug in the fan hub in the motherboard, not the case (the latter BTW being the Lian-Li O11 dynamic XL). Thanks for any help concerning choice of fan hub(s) and proper plugging (CPU fan connector, CPU OPT fan connector, Chassis fan connector ???).
 
Fan hubs will usually plug into the main CPU fan header, to get the PWM signal. They have a SATA (usually) power connector as well, to power the fans, so you won't be sucking too much power from the motherboard headers.

I have 12 fans in my rig...:D I use a cheap Thermaltake 10-way PWM hub (Commander FP), cost less than a tenner and it works fine. There isn't currently anything 10-way I can see on OCUK, so I can't provide a link, I'm afraid. You'll have to do your own rummaging...

Two-way PWM splitter cables are also a good thing to have a couple of knocking around. If a tidy system is your thing, grab a couple of fan extender cables too. To begin with, I had fan cables coming from all over the case, with the hub actually dangling in the middle of the case by the wires...
 
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Thanks for the reply. So basically I could hook up all the 7 bequiet! fans in let's say a Commander FP hub that I plug in the CPU fan header. Then what should I do with the CPU fans ? Use a Two-way PWM splitter cables and hook them up in the Commander FP hub too ? (Won't that create an Ampere overload?). Or could I plug them in the CPU OPT Fan connector ? (What's this anyway ? Optional ? Optical?).
Alternatively, would this hub do the job too : DEEPCOOL FH-10 Integrated Fan Hub ? https://www.amazon.com/DEEPCOOL-FH-...rds=DEEP+COOL+FH-10+Hub&qid=1590825240&sr=8-1
 
Yes, you could use the CPU_OPT header, or the hub itself. Two fans running off a splitter from the hub shouldn't cause a problem, but you still have spare mobo headers too- you could still use the chassis fan headers as intended, rather than running every fan through the hub.
For instance, I have six radiator fans, two front intakes and two top intakes running off the hub, with the two rear exhausts running on chassis fan 1 & 2 sockets. Bear in mind that although you can control the hub fans' speed, they will all move together.
Using mobo headers for individual fans means you can set different profiles for them.

Nothing stopping you from using CHA_FAN3 for the CPU fan if you want to :D
 
Thanks. I understood there was a difference for being able to control PWM fan speeds if I were to use either the CPU ones or the Chassis ones. Is that correct ? What's the difference ? Could I plug the CPU fans with a splitter in the CPU_OPT header (what does this stand for anyway?).
Any thoughts (pro or con) related to the other hub I found ?
 
From my personal experience, I've found that hubs seem to like being in the CPU header- although I think this is more dependent on the mobo than the hub, some use 'faux-PWM' on the chassis fan, with the proper PWM signal only on the CPU header. The CPU OPT header is usually a daisy chain from the CPU header, so they are adjusted as one in the BIOS- so you can use either or both.

Afaik it just stands for 'optional'- an extra fan if you need it! Can't see any particular issue with what you suggest, as long as you're happy for the CPU fans to move in step with those on the hub.
 
ioverclockers said:
Thx for the reply, which made me aware of a typo in my first post. I actually meant where do I have to plug in the fan hub in the motherboard, not the case (the latter BTW being the Lian-Li O11 dynamic XL). Thanks for any help concerning choice of fan hub(s) and proper plugging (CPU fan connector, CPU OPT fan connector, Chassis fan connector ???).
Click to expand...
Plug hub or fans to headers using temp of component you want fans to be speed controlled for. I setup case fans supplying GPU with cool air to cycle based on GPU temp and fans supplying CPU on headers. Your motherboard manual should tell you what temps control curves for what fan headers. As guide says, remove all PCIe back slot covers to increase rear vent area around GPU for better front to back airflow thus lower air temp so fans don't have to spin as fast making things quieter.

As DoneADougalOnSofa said, CPU opt is just another CPU fan header. Keep in mind not all 4-pin headers are PWM, and PWM fans iplugged into variable voltage headers are still still speed controlled. But plugging a PWM splitter / hub with PSU power into a variable voltage header and fans will run full speed all the time.

Be careful about using too many fans and ending up with what I call air blow instead of air flow. key to good cooling and low noise levels is supplying components with cool air, not blowing air everywhere mixing heated component exhaust with cool intake air. I almost never use case exhaust fans. Using both intake and exhaust case fans is like using push / pull on coolers and radiators; very little if any difference in temps but more fans make more noise. Cases almost always have more exhaust vents then intake vents with fans, and about 150% more intake fan area than component fan area. Keep in mind 2 fans on CPU cooler in push / pull only have 1x fan of airflow. 3x 80/90mm GPU fans flow about 2x 120mm fans or 1.5 140mm fans of intake airflow. In other words, 3x 140mm good pressure rated intake are all the case fans that are needed. Sometimes I run 4x 120 or even 4x 140 with 3x in front and 1x in bottom so they can run slower and still supply all the air components need.
 
Looking again at your fan list, my recommendation would be this:

CPU cooler fans on splitter from CHA1 header
SilentWings run from the hub, CPU header
BL070 from CHA 2 and 3, with splitter cable for three fans.

This would allow most control over the speed profiles, although you could run the CPU fans off CPU_OPT instead, and do without a second splitter for the chassis fans.

That's probably what I'd do. In fact it's pretty close to what I have done!

Get it wired up, then just hit the auto-calibration in the BIOS.
 
thanks again for ur feedback ! As a matter of fact the BLO70 is a part of the SilentWings, not a different set of fans. So ok, I'll go with the hub you suggested.
Last little question : I had already bought a pack of two Noctua NA-SYC1 4-pin Y-cables, but they're a bit short honestly. So wanted to know what fan extender cable you would suggest to have some more leverage inside the case.
 
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Google is your buddy for cable extensions. Google for "pwm fan extension cable" and you should find a five pack for three quid delivered..
 
doyll said:
Be careful about using too many fans and ending up with what I call air blow instead of air flow.
Click to expand...
Thanks for the breakdown. Well, seems to be a tricky business after all, as I said. Basically, what I had in mind is to have a vertical setup with 3 120mm intake fans on the bottom and the same on the top for exhaust, adding one exhaust fan to the mix at the back. I also intend to have a vertical GPU setup with a PCIE extender cable, so as not to concentrate too much hot air between the CPU and GPU, allowing it to diffuse a bit better in the case (The dynamic XL is quite a large case). Hope it'll work out all right this way...
 
Bottom to top airflow will move heated exhaut air coming off of GPU up and into CPU cooler. I would use 3x in right side and 1x bottom intakes, remove all PCIe back slot covers to increase rear vent area for better front to back flow, block off other bottom opening so air intakes push into case has to flow though case and out instead of leaking out and being drawn back into fans. This layout gives front to back airfllow so GPU heated exhaust moves back and out instead of up into CPU airflow. 4x Silent Wings 120mm 3 PWM is all the fans you need.

Hot air rises is a myth in our cases. Even the weakest fan at low speed will overpower any upward movement of warmer air, and cases do not have the tall tower to small diameter of a smoke stack so no chimney effect.

More fans make more noise:
Noise level increase Δ L for n equal loud sound sources

number
of fans . . . . dB increase
1 . . . . . . . . . . 0.0
2 . . . . . . . . . . 3.0
3 . . . . . . . . . . 4.8
4 . . . . . . . . . . 6.0
5 . . . . . . . . . . 7.0
6 . . . . . . . . . . 7.8
7 . . . . . . . . . . 8.5
8 . . . . . . . . . . 9.0
9 . . . . . . . . . . 9.5
10 . . . . . . . . .10.0
12 . . . . . . . . .10.8
16 . . . . . . . . .12.0
20 . . . . . . . . .13.0

I'm interested in your thoughts of Zalman CNPS20X, like ease of install, quality of mount and cooler, fan sound profile, etc. I suspect it will be a good cooler.
 
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Almost all fan hubs have supplemented power from either molex or sata power cable so you don't have to worry about amps or volts from the mother board. The motherboard would just be for adjusting the speed of the fans.
 
doyll said:
I would use 3x in right side and 1x bottom intakes, remove all PCIe back slot covers to increase rear vent area for better front to back flow
Click to expand...
Wow! That sounds rather radical (albeit logical...). So how can I deal with a all my PCIE hardware ? Sounds like I'm gonna have to have extenders all over the case in this scenario ... One of the reasons for the vertical GPU mount was precisely to enable some lateral exhaust from the back before hitting the CPU. Forgot to mention that I intend to use a GPU cooler (the Morpheus II, which has good reviews) in order to reduce GPU (Vega 64) heat output.
How about doing the opposite ? I mean using the back and bottom for air intake (4 120mm in all) and exhaust in front thru 3 120mm ? Have to check whether this is doable with the Dynamic XL.
As to the Zalman, yea, I doubted between this and the king of the hill Noctua one, but Zalman got slightly better temps (not much, like 1 or 2°C) and just wanted to give it a shot. Will update on how that went.
For those willing to wait out a bit, I'd recommend the IceGiant ProSiphon Elite https://www.icegiantcooling.com, which seems one of a kind of a cooler. Initially scheduled for release this month (May) it's being pushed back to September. They will have an aluminium edition first, but will improve on the design with a copper edition in 4Q. If I were to change my Zalman, it'd be for this one for sure...
 
Please define 'all my PCIe hardware'.

Vertical GPU mount usually improves cooling and seperation of heated exhaust from cool intake airflow.

Simplest reasons are back doesn't have 3x 120mm vents to use with intake fans, or filters.

Honestly NH-D15 is not "king of the hill" but one of many kings. There are many others equally as good like all Thermalright Silver Arrow variants, TRUE Spirit 140 Power (£50 if available), Le Grand Macho, Noctua NH-D14, Phanteks PH-TC14PE (£53 but out of stock), Cryorig R1, Scythe Fuma, Alpenfohn Olymp, be quiet! Silent Rock Pro 3, Deepcool Assassins', and many others all within a couple degrees of each other with same fans.

We haven't even seen IceGiant ProSiphon Elite final product yet, only prototypes. And the prototype has only been tested once (by tom'shardware) against NH-U14S which is at best a few degrees hotter than best top tier air coolers. Also it is designed for extreme heat load cooling and doesn't perform as well with less heat to remove, not going to perform as well as existing coolers in applicatons like most of us use. Adding to these issue is it's shape makes it much harder to fit into normal applications, and it's optimum orientation is with motherboard horizontal, used in towers it won't perform as well.
 
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doyll said:
Please define 'all my PCIe hardware'.
Click to expand...
Well, 1x wifi/bt module and 2x 4usb port adapters.

But looking again at the case on the product page https://www.lian-li.com/pc-o11d-rog/, I see that a horizontal airflow won't be working, as there is no way to mount fans on the front panel. On the other hand, it is possible to fix them on the lateral panel. Now I'm also not sure whether I have to remove all the PCIe back slot covers in order to be able to vertical mount my GPU (?). Anyway, basically these are the options for fan placement : (all are 120 mm except the CPU fans) : 1 rear, 3 bottom, 3 top and 3 lateral. In such a scenario, what would be the best fan intake and exhaust placement ? Would it better to opt for lateral intake and bottom (and rear) exhaust or top intake and bottom exhaust (both would reduce amount of hot CPU air blowing towards the GPU)? I'm just wondering though whether in such a scenario the hot air that's exhausted from the bottom once out of the case won't whirl up again for the intake lol... Thanks for any further suggestions for proper placement.
Thanks for ur thoughts on the pro siphon. Puts things in perspective.
 
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Indeed, mount intakes over vents in right panel near front of case. Removing PCIe back slot covers increases rear venting a lot. Even vented slot covers restrict airflow to less than half what open slots flow. ;) As I've said, exhaust fans only add noise. Sure, at same fan speed temps may be a couple degree cooler with exhaust fans, but in just intake fans' speed is increased to same noise level as both intake and exhaust make cooling is the same. The straighter the airflow the less turbulence / the less heated air mixes with cool intake airflow and the better the cooling temps. Best way to know is experiment and monitor the air temp entering cooler with a cheap wire lead remote sensor digital thermometer like basic indoor/outdor digital themometer, terrarium / aquarium or fridge remote sensor thermometer. Search for "wire lead remote sensor digital indoor/outdoor thermometer" or similar should find some for about seven quid, then set it up like at end of link below:
https://forums.overclockers.co.uk/t...-i-put-my-temp-sensor.18564223/#post-26159770
 
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