Jump to content

How many fans are too many?

Revanchist1ab
By Revanchist1ab
in Cooling
 Share
Posted

Simple question. I'm lining the top of a mid-size with fans.

 

Should I use two ($20) 140mm fans or three ($12) 120mm fans?

 

Ignore cost difference. Case is a Cougar Panzer-S.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

So, I imagine the differences are actually negligible but someone on Youtube has probably tested it to see so have a search.

|| Processor: AMD Ryzen 5 2600 || RAM: 32GB (4x8GB) Corsair DDR4 Vengance (3000) || Motherboard: ASUS Prime B450-Plus || Graphics Card: Gigabyte RTX2070 || Storage: 750GB SSD (2 Drives), 3TB HDD (2 Drives) || Case: NZXT H500 || Power Supply: be quiet! Pure Power 11 600W || 

 

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
4 minutes ago, Revanchist1ab said:

Simple question. I'm lining the top of a mid-size with fans.

 

Should I use two ($20) 140mm fans or three ($12) 120mm fans?

 

Ignore cost difference. Case is a Cougar Panzer-S.

I’d go 3 for aesthetics.

 

go check the amount of air per second for your fans and add them up to see which is more, most likely 3.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

About 10 CFM more with the three but 8 dB higher. I save like $4 going with the three and they technically cover more area. Neat; thanks guys.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

Hi, I'm building a Ryzen 7 system with either a ASRock Steel Legend or MSI MPG Gaming Plus X570 board in a Cougar Panzer-S case.

 

The case comes with the front 3 fans but none on the top, back, or bottom. I'm gonna be using the stock AMD cooler and a 3-fan 2080 Super graphics card.

 

Currently, I'm planning on adding 5 additional ($12) 120mm fans. 3 on top, 1 in back and 1 on the bottom.

 

Thoughts?

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

There's no such thing. :3

 

But if you're trying to figure out if spending money on more is worth while or not: figure out what temps you can get with your current setup after testing various configurations and settings. If the temperature is still not to your liking, add more fans.

I have a blog! And a list of guides I've posted

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

Having 1-2 fans in the front and 1 in the back is enough for good airflow. Of course, how many you'd want depends on your situation: is your case too small or too hot? Do you use a CPU watercooler? Do you mind the noise all these fans will make?

 

Also, try not to add more exhaust fans than intake fans. Always keep an equal number or a 2-to-1 ratio of intake-to-exhaust fans, so that the air pressure is optimal.

 

And be aware that 3+5 fans will probably result in an extremely noisy rig. If you don't care about that, go for it.

Moonstone -- MSI B450 Tomahawk • Ryzen 5 3600 • Gigabyte RTX 2060 G. OC Pro 6GB • 16GB HyperX Fury Black • Corsair CX550M • Aerocool Cylon

Peripherals: Dell P2719H 27'' @ 1080p + Acer VA270H 27'' @ 1080p • Redragon Mitra RGB Red Switch • Superlux HD681 • Logitech Z207

Storage: WD Black SN750 500GB NVMe SSD + Kingston A400 480GB SSD + Seagate Barracuda 1TB HDD

Rebound 95 -- PC Chips M519 Socket 7 AT Mobo • Pentium P54C 100Mhz • Cirrus Logic GD3454 1MB GPU • Creative L. Sound Blaster 16 CT2950 • 8MB of RAM

(Check my albums for pictures of the systems)

 

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

Sooo... if the 3 in the front and the 1 on the bottom are intake, then I'll need 2 exhaust fans. So maybe 1 140mm on top and 1 120mm in the back.

 

Thank you all!

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

Besides adding a rear exhaust, the extra money is probably better put towards a better cpu cooler if you want better cooling. 

More fans than necessary aren't going to make much of a difference in cooling.

 

If you ever need help with a build, read the following before posting: http://linustechtips.com/main/topic/3061-build-plan-thread-recommendations-please-read-before-posting/
Also, make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

@WoodenMarker Well, if I cut both the top and the bottom fans, that would only give me an additional $30 towards a better CPU cooler. Though, it would forsake the AMD cooler, taking that value away.

 

Looking at both liquid cooled and non, it would be about $110 for a decent (not cheapest) liquid cooler and about $60 for a decent physical cooler that could match the other three fans that were sacrificed (top,bottom,CPU).

 

I would of course, want the best cooling, but there just doesn't seem to be too much value in giving up three fans for one, unless I'm missing something.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
3 minutes ago, Revanchist1ab said:

@WoodenMarker Well, if I cut both the top and the bottom fans, that would only give me an additional $30 towards a better CPU cooler. Though, it would forsake the AMD cooler, taking that value away.

Looking at both liquid cooled and non, it would be about $110 for a decent (not cheapest) liquid cooler and about $60 for a decent physical cooler that could match the other three fans that were sacrificed (top,bottom,CPU).

I would of course, want the best cooling, but there just doesn't seem to be too much value in giving up three fans for one, unless I'm missing something.

Which cpu / cooler are you using? Where are you shopping / located?

There are plenty of 30 USD coolers that would outperform even the Wraith Prism and easily make a bigger difference to temps than adding top fans. 

If you ever need help with a build, read the following before posting: http://linustechtips.com/main/topic/3061-build-plan-thread-recommendations-please-read-before-posting/
Also, make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

Thank you for your help.

 

The build (currently) will be using the standard AMD CPU cooler that comes with the Ryzen 7, the three fans on the front of the Panzer-S, a Fractal Design HF14-BK 118.2 CFM 140 mm fan (on top), and two be quiet! Pure Wings 2 120 PWM 87 CFM 120 mm fans (bottom and rear).

 

I am currently located on the East Coast of the United States (UTC-5) and I use PartsPicker partially due to laziness and a want to streamline my searches.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
32 minutes ago, Revanchist1ab said:

The build (currently) will be using the standard AMD CPU cooler that comes with the Ryzen 7, the three fans on the front of the Panzer-S, a Fractal Design HF14-BK 118.2 CFM 140 mm fan (on top), and two be quiet! Pure Wings 2 120 PWM 87 CFM 120 mm fans (bottom and rear).

I am currently located on the East Coast of the United States (UTC-5) and I use PartsPicker partially due to laziness and a want to streamline my searches.

For some reason, I didn't assume you weren't going with a 1700 / 2700 which meant the cooler might've been a Wraith Spire as opposed to a Prism. 

If you want lower noise or improve cooling, the Macho Direct is a good option: https://pcpartpicker.com/product/TsL7YJ/thermalright-cpu-cooler-machodirect

If you really want more fans, NF-P12 / P14S' would probably be better and the biggest benefactor would be the graphics card.

https://pcpartpicker.com/product/VNBTwP/noctua-nf-p12-redux-1700-pwm-708-cfm-120mm-fan-nf-p12-redux-1700-pwm

https://pcpartpicker.com/product/8r9KHx/noctua-case-fan-nfp14sredux1500pwm

 

Make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

If you ever need help with a build, read the following before posting: http://linustechtips.com/main/topic/3061-build-plan-thread-recommendations-please-read-before-posting/
Also, make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

@WoodenMarker A question on air flow and case fan-type choice.

 

If you do see this, please read to the end as this gets complicated. My apologies in advance.

 

The Panzer-S comes with 3 airflow fans in the front (orange CFD series LED fans). As the case has no internal position for a CD drive or HDD mounts between the front of the case and the motherboard, the 3 airflow fans would be the optimal choice to push air into the case, correct? From research online, you want airflow fans for more air and static pressure fans if you're trying to push air past an obstruction. This is why you see them on CPU coolers (from what is said online).

 

Both Noctua fans you recommended looked to be static pressure fans with pressure readings above the others and with less airflow (due to them being static pressure type).

Was this a choice to adjust the static pressure in the case?

 

With the exception of the bottom fan, which I might agree now should be a static pressure fan as its trying to pull air in from a tight position, shouldn't the top and rear additional fans be air flow fans? I've been trying to find talk of this on the forums, but I'm not finding much in regards to this topic.

 

Is there a static pressure value I should aim to hit?

 

Due to the airflow of the Panzer-S, my plan now would be to keep the 3 pre-installed airflow fans on the front, add 1 static pressure fan to the bottom, 1 airflow fan to the rear, and one airflow fan to the top. (If need be, later down the line I would replace the stock Wraith Prism cooler with a better Noctua cooler).

 

After doing airflow calculations, should I actually add more? Maybe remove the bottom fan and replace it with an additional 140mm up top?

  • Without removing the bottom fan, adding an additional 140mm would result in an exhaust total of 323.4 CFM with a net positive of 75.61 CFM instead of 193.81 CFM as shown in current calculations.
  • If you DID remove the bottom case fan and keep the 2 top 140mm fans the result would be a net positive of 4.86 CFM. Research online suggests you want a "slight" difference in CFM, but I could not find a more specific calculation or value suggestion.

Airflow calculations:
Intake:
3 120mm CFD fans:                5.22 mmH2O / 328.26 CFM max
1 120mm NF-P12 (bottom):     2.83 mmH2O / 70.75 CFM
total:                                        8.05 mmH2O / 399.01 CFM max

 

Exhaust:
1 140mm FD HF14-BK:           0.95 mmH2O / 118.2 CFM
1 120mm bQ Pure Wings 2:    1.25 mmH2O / 87 CFM max
total:                                        2.20 mmH2O / 205.2 CFM max

 

Intake CFM - Exhaust CFM = 193.81 CFM

 

While not an exact calculation, due to the dust levels of my home, I believe I will need positive airflow. I do understand CFM calculations are much more complicated, but there doesn't seem to be many walkthroughs on it. If you read this all the way through, you already have my thanks for considering this quandary.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
4 minutes ago, Revanchist1ab said:

3 airflow fans would be the optimal choice to push air into the case, correct? 

Both Noctua fans you recommended looked to be static pressure fans with pressure readings above the others and with less airflow (due to them being static pressure type).

With the exception of the bottom fan, which I might agree now should be a static pressure fan as its trying to pull air in from a tight position, shouldn't the top and rear additional fans be air flow fans?

 

Is there a static pressure value I should aim to hit?

 

Airflow calculations:

total:                                        8.05 mmH2O / 399.01 CFM max
total:                                        2.20 mmH2O / 205.2 CFM max

Intake CFM - Exhaust CFM = 193.81 CFM

All fans have some degree of both airflow and static pressure. Optimizing for one often results in not being as optimal for the other. What's considered an airflow or static pressure fan is arbitrary and dependent on how it compares to other available fans. An 'airflow' fan isn't necessarily better in an unobstructed environment just because it's an airflow fan. Some fans are just better than others. 

 

The NF-P12 / P14S veer towards static-pressure optimized designs but that doesn't mean they don't deliver great airflow. You seem to be aiming for overkill airflow so the NF-P12 / NF-P14S will allow for better performance over the HF-14 and PW2's. If you weren't going for overkill, a single NF-S12B or NF-S12A would very quiet and be plenty for rear exhaust which is all you'd really need.

As you've mentioned, the bottom of the case, psu shroud, and positive pressure from the front intake restrict the bottom quite a bit so more static pressure can help there. 

 

The top of the case doesn't seem very restrictive but it's probably enough to inhibit the HF-14's extreme design. 

CoolingTechnique has an example here of how the performance tanks even with a bit of restriction: http://www.coolingtechnique.com/recensioni/air-cooling/ventole/1654-recensione-fractal-venturi-serie-hf-e-hp.html?start=6

Spoiler

pressure_14.png

No, there isn't a static pressure value to hit for system airflow. Static pressure is localized to where the fan is being used and drops off dramatically as the air moves away from the fan.

If you're just aiming for positive pressure which can help reduce dust accumulation, any of the mentioned configurations would be fine for that. 

If you ever need help with a build, read the following before posting: http://linustechtips.com/main/topic/3061-build-plan-thread-recommendations-please-read-before-posting/
Also, make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

@WoodenMarker Hmmm... If you insist, I'll swap out the current fans for the two Noctuas. Price is only a $10 jump so it's not gonna hurt.

 

I'll be putting two 140s on top and a 120 in the rear and bottom.

 

Thank you again, for the help.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
1 hour ago, Revanchist1ab said:

@WoodenMarker Hmmm... If you insist, I'll swap out the current fans for the two Noctuas. Price is only a $10 jump so it's not gonna hurt.

I'll be putting two 140s on top and a 120 in the rear and bottom.

If there's anything I'm insisting, it'd be to just get a single rear exhaust and see how performance is before deciding on whether or not to order any new fans or a new cooler. 

If you're still going with more fans, I'd only use a single 140mm at the top so it doesn't remove any fresh air that could've went to the cpu cooler first. 

If you ever need help with a build, read the following before posting: http://linustechtips.com/main/topic/3061-build-plan-thread-recommendations-please-read-before-posting/
Also, make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
On 8/29/2019 at 2:05 PM, Revanchist1ab said:

Simple question. I'm lining the top of a mid-size with fans.

 

Should I use two ($20) 140mm fans or three ($12) 120mm fans?

 

Ignore cost difference. Case is a Cougar Panzer-S.

I've used both of these packs, so coming from pure experience I'd say go with what your use case is. Two 140mm would fill the case with air with less RPM which means less noise. Or three 120mm fans with slightly higher noise and higher versatility in cases. In my experience I would reccomend saving up for more quality fans as these type of cheap fans get noisey. I've had 8 go had on me. 

Setup No. 1: CPU: AMD Ryzen 2200g @ 3.95GHz GPU: EVGA GeForce GTX 780 3GB Dual FTW w/ EVGA ACX Cooler MOBO: MSI B350 Tomahawk Gaming Motherboard RAM: KingSpec DDR4 8GB Single Channel @ 2866MHz PSU: CS Series Modular CS 650M - 650 Watt Power Supply 80+ Gold Efficiency CASE: EVGA DG-73 STORAGE: 240GB Inland SSD, 320GB 7200 RPM Western Digital Hard Drive COOLER: Cooler Master ML240L - 240mm Liquid AIO MONITORS: 1x Dell 1920 x 1080p 24" Widescreen 60Hz, 1x Dell 1920 x 1080p 22" 60Hz KEYBOARD: Cheap Inland USB Keyboard MOUSE: 2400DPI Anker Gaming Mouse RGB CHAIR: Ikea MARKUS Office Chair 

 

Setup No. 2: CPU: Intel i5-4950 GPU: Powercolor Red Devil RX 570 4GB VRAM MOBO: Asus B85 RAM: Ripjaws 8GB DDR3 @ 1333MHz Single Channel PSU: Insignia 450 Watt 80+ Efficiency Power Supply CASE: Thermaltake Versa N21 STORAGE: Samsung 860 EVO 240GB SSD COOLER: bequiet! Pure Rock Slim MONTIROS: 1x HP 24" 1680 x 1050p 60Hz KEYBOARD: Apple USB Keyboard MOUSE: Anywhere MX Logitech Mouse

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
32 minutes ago, Ciuwas said:

I would reccomend saving up for more quality fans as these type of cheap fans get noisey. I've had 8 go had on me. 

By cheap fans, are you referring to stock case fans in general or Cougar's CFD / Dual-X's? The latter are easily better than most stock case fans. 

If you ever need help with a build, read the following before posting: http://linustechtips.com/main/topic/3061-build-plan-thread-recommendations-please-read-before-posting/
Also, make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

Link to comment
Share on other sites
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing Cooling

×