[SOLVED] I have bought 5 Cooler Master Jet Flo 120 fan and something really bothers me.

[handsomejack]

A test conducted by Overclockers
A test conducted by DVtests

• So I used 3 as front intake, 1 in the rear for exhaust, and 1 as the replacement of my fan mounted on DeepCool Gammaxx 300 CPU cooler.

My concern is that I m not sure about whether the replacement of the CPU cooler fan worth...

The original fan on my Gammaxx 300 is quiet even during the full speed of ~1600rpm.

Theoretically, it can generate ~55.5CFM and ~around 2.03 mmAq at full speed.

For the new Cooler Master Jet Flo 120 fan, it generates ~95cfm at 2000rpm.

According to the test conducted by Overclockers and DVtests, it can even generate more than 110cfm at full speed and 2.72-2.99mmAq(from Cooler Master website).

However, because of the huge noise generated by the fan at full speed, I set the rpm to varies between 1200-1600.

As far as I know, apart from the cfm value the higher the magnitude of static pressure it generates the more air can penetrate through the cooling fin which provides a better cooling ability.

Well, the original Gammaxx 300 fan generate 2.03 mmAq and ~55.5CFM at 1600rpm and still very quiet.

However, at 1600rpm the Jet Flo 120 starts to become noticeably noisy. It is the low-frequency humming sound that makes it noisy.

I set it to 1200rpm most of the time since the noise will be noticeable once exceeded it, and 1600rpm only when CPU getting super hot.
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The question is, with the original fan I can always set it to 1600rpm all the time because it is just so quiet but with the Jet Flo, I can only

stick to 1200rpm most of the time. At 1200rpm, Jet Flo can still generate ~65cfm which is great! but what about the static pressure it generates?

After searching for some time on the internet, I still can't find anyone who has tested the static pressure of Jet Flo at 1200rpm or 1600rpm.

Are there any equations to calculate or graphs about it? or can anyone estimate the static pressure of it at 1200rpm and 1600rpm?

What do you guys think? Is the replacement worth it or not?

sorry for my poor English, I hope everyone can understand what I'm saying.

 

[Phaaze88]

You'd have to get that(fan curves) info from Cooler Master themselves. CFM, static pressure, and noise level do NOT scale linearly.

Stronger and faster fans do not automatically equate to better; in some situations, it's actually worse.
I'd imagine the engineers know more than you do, and have already selected the best fans - from the company's inventory - for the job.
The size of the heatsink and the size of the gaps in the fins are optimized for the fans they came with.

Silver Arrow IB-E Extreme Rev. B: some high speed fans here. Heatsink fins have a gap of 2mm.
Le GRAND MACHO RT: fan speed here is quite low. Heatsink fins have a gap of 3mm.
Swap the fans, and they'd both perform worse.

Same deal with a liquid cooler with high rpm fans - say someone decided to put some slower fans on, because the originals got to loud.
Or the popular Corsair H150i Pro with it's rather moderate rpm fans.

I personally experimented replacing the 2 NF-A15 on my NH-D15S with IPPC 3000s: it did so little for actual cooling, but I got a crap-ton more noise for it!

I kinda suck at explaining things: it has to do with the degree of resistance created by the heatsink/radiator.
The large gaps in coolers like the Le Grand Macho RT and the H150i Pro already allow plenty of air to flow through them; faster fans will do little, or they may even cause some kind of backflow to occur.
Then there's the other coolers mentioned: slower fans generally don't have enough 'umph' to move air though the tighter restrictions.


All that, and I wouldn't be surprised if Cooler Master used some cheap motor in those Jet Flos...

TL;DR: no, the replacement isn't worth it. Besides, aren't the Jet Flos chassis airflow fans, meaning they're not ideal for heatsinks and radiators?

 

[handsomejack]

You'd have to get that(fan curves) info from Cooler Master themselves. CFM, static pressure, and noise level do NOT scale linearly.

Stronger and faster fans do not automatically equate to better; in some situations, it's actually worse.
I'd imagine the engineers know more than you do, and have already selected the best fans - from the company's inventory - for the job.
The size of the heatsink and the size of the gaps in the fins are optimized for the fans they came with.

Silver Arrow IB-E Extreme Rev. B: some high speed fans here. Heatsink fins have a gap of 2mm.
Le GRAND MACHO RT: fan speed here is quite low. Heatsink fins have a gap of 3mm.
Swap the fans, and they'd both perform worse.

Same deal with a liquid cooler with high rpm fans - say someone decided to put some slower fans on, because the originals got to loud.
Or the popular Corsair H150i Pro with it's rather moderate rpm fans.

I personally experimented replacing the 2 NF-A15 on my NH-D15S with IPPC 3000s: it did so little for actual cooling, but I got a crap-ton more noise for it!

I kinda suck at explaining things: it has to do with the degree of resistance created by the heatsink/radiator.
The large gaps in coolers like the Le Grand Macho RT and the H150i Pro already allow plenty of air to flow through them; faster fans will do little, or they may even cause some kind of backflow to occur.
Then there's the other coolers mentioned: slower fans generally don't have enough 'umph' to move air though the tighter restrictions.


All that, and I wouldn't be surprised if Cooler Master used some cheap motor in those Jet Flos...

TL;DR: no, the replacement isn't worth it. Besides, aren't the Jet Flos chassis airflow fans, meaning they're not ideal for heatsinks and radiators?

I don't know... I thought the Jet Flo are both high pressure and airflow.. on paper at least. That's why I decided to put one on the heatsink and gave it a try. I guess it is not bad for a case fan since it does move a lot of air(65cfm at 1200rpm) and be able to provide enough static pressure to move the air through the filter into the case, it still generates ~46 cfm with a filter at 1200rpm. Anyway, thx for your reply.

 

[Phaaze88]

Glad I was able to provide some insight into the matter.

https://www.coolermaster.com/catalog/legacy-products/cooling/jetflo-120/#overview
Yeah, these are really chassis airflow fans.
Looks like I was right about the motor - it's their own design:
POM Bearing - Cooler Master 4th Gen. bearing (*POM: Polyoxymethelene)

The Gammaxx 300 uses some hydro bearing fans - looks like they don't make the fans for that one anymore though.

 

[handsomejack]

well...
believe it or not, I just tested it and the default fan on gammaxx 300 is actually a lot greater than the jet flo 120...

with 2mmAq and 55.5 CFM at full speed, this fan is quiet and not bad~

Jet Flo is indeed a very strong fan but very noisy and can only show its full potential at high rpm which will be

too loud for normal operation or even gaming.

 

[Phaaze88]

I believe you alright; I'm looking at the spec page.
Fairly moderate max rpm and fairly quiet compared to the Jet Flo.

 

[handsomejack]

I believe you alright; I'm looking at the spec page.
Fairly moderate max rpm and fairly quiet compared to the Jet Flo.

Well, man...so after a while,
I finally decided to sell all of my Jet Flo 120 fans out.
I have bought 3 Noctua NF-P12 fan for intake and 1 NF-S12 fan for exhaust.
Oh man... the Noctua fan is so quiet yet producing quiet a lot airflow and static pressure to cool down my system.
Although it is quite expensive it actually worth the price, you can't hear <Mod Edit> even if you put your ear near the fan.

 

[Phaaze88]

Well, man...so after a while,
I finally decided to sell all of my Jet Flo 120 fans out.
I have bought 3 Noctua NF-P12 fan for intake and 1 NF-S12 fan for exhaust.
Oh man... the Noctua fan is so quiet yet producing quiet a lot airflow and static pressure to cool down my system.
Although it is quite expensive it actually worth the price, you can't hear <Mod Edit> even if you put your ear near the fan.

Nice!
I'm actually waiting on a few S12As to arrive so I can replace the Fractal Design Dynamic X2s on this AIO; they are fairly louder than all the other Noctua fans in there currently.