Need better fans... Help!

[nervx]

Just built a new system and it's not as quiet as i had hoped. Specs:

-Antec Mini P180
-ASUS P5E-VM HDMI
-E8400
-EVGA E-GEFORCE 9800GTX
-Thermalright ULTRA-120 Extreme + Scythe S-FLEX SFF21E
-Corsair XMS2 Dominator
-Two WD Caviar SE16 WD6400AAKS
-Corsair 620W

Today i went through the fans and listened to each one to find the source of the noise. The problems were the 120mm tricool on the back and the SFF21E. the 200mm is set to low and there is no fan in the front.

the 120mm tricool even set on low isnt quiet so it has to go.

the SFF21E is the biggest problem. it creates a sort of whistle/buzz when on the thermalright. take the fan off and the noise stops. slow the fan down to around 800rpm and the noise stops... i held my nexus up the the heatsink to see what would happen and the noise wasnt there....wtf? why does it do this?

So question is what fans should i replace these two with. I was thinking 800rpm fans but which ones? What about for the thermalright... would 800rpm fan be enough?

[thejamppa]

800 RPM fan is more than enough unless you have some crazy OC on tremendously hot chip. E8400 even OC'ed is not hot chip so 800 RPM fan is more than enough.

Its weird. My Schte S-Flex E is whisper quiet on my SI 128 SE. Maybe you have a bad sample?

[nervx]

Its weird. My Schte S-Flex E is whisper quiet on my SI 128 SE. Maybe you have a bad sample?

it's odd though it only makes the sound when on the thermalright. so im guessing it's from the air passing through that creates the whistle/buzz. odd that the nexus doesnt create the same sound though.

[porkchop]

use the sflex as the exhaust and put the nexus on the thermalright?

an antec tricool rigged to 5v and set on med is very quiet(starts fine too), but moves very little air- this may be enough for the processor though.

[Felger Carbon]

the SFF21E is the biggest problem. it creates a sort of whistle/buzz when on the thermalright. take the fan off and the noise stops. slow the fan down to around 800rpm and the noise stops... i held my nexus up the the heatsink to see what would happen and the noise wasnt there....wtf? why does it do this?

The SFlex is about the highest-pitch 7-blade 25mm-thick 120mm fan around, short of the Noctua. The Nexus is the lowest-pitch one I know of. Low-pitch fans handle backpressure better than high-pitch, and the U120 HS generates a lot of backpressure. Your setup is almost a perfect demonstration of the need to account for high backpressure when it's present.

Might be some sample-variance in the act as well, which is why I wrote "almost perfect".

[nervx]

use the sflex as the exhaust and put the nexus on the thermalright?

an antec tricool rigged to 5v and set on med is very quiet(starts fine too), but moves very little air- this may be enough for the processor though.

yeah im going to try the sflex as exhaust and nexus on the thermalright on thursday and see how it is.
is it possible to use the 3-speed fan switch on the 180mini case with the sflex? im afriad it might be just as loud do to the air flow but if the switch can slow it down to around 800 it would save me some money.

Felger Carbon what causes backpressure and how to i fix it? sounds like my nexus would be the best solution save for maybe going down to 800rpm correct?

[porkchop]

The SFlex is about the highest-pitch 7-blade 25mm-thick 120mm fan around, short of the Noctua. The Nexus is the lowest-pitch one I know of. Low-pitch fans handle backpressure better than high-pitch, and the U120 HS generates a lot of backpressure. Your setup is almost a perfect demonstration of the need to account for high backpressure when it's present.

really very interesting.

is it possible to use the 3speed fan switch on the 180 case with the sflex?

i don't think so- from what i can tell, the controller is just a casing for the tricool fan controllers.

[Felger Carbon]

[...what causes backpressure and how to i fix it? sounds like my nexus would be the best solution save for maybe going down to 800rpm correct?

The rated noise and CFM of fans (when measured instead of "Thermaltaked" by the advertising weenies) is measured under completely free-air conditions. No impediment to airflow anywhere. Run a fan in open air, holding the fan in your hand, unmounted. Bring the palm of your other hand towards the intake side of the running fan. Two things will happen: the noise will increase, and the CFM will decrease. The closer your hand, the more backpressure and the more noise and less CFM.

Regrettably, one commonly runs into *some* backpressure in an actual computer case. As you have discovered, mounting a fan on a HS with closely spaced fins does a fine job of generating backpressure. The filters Bluefront has to use on all his computers are even better.

Even more regrettably, there is absolutely no industry standard method of measuring this effect. Here at SPCR, I've proposed a method, and Bluefront has used a method that depends on human judgement instead of a sound level meter (or some such) to judge results.

The "best" solution for you is the one which produces acceptable (to you) cooling with the lowest noise level, or acceptable noise with the best cooling. Turning down the SFlex to 800 meets your noise requirements, which is good, but the Nexus might also do so while providing better cooling. In that event, running the SFlex at 800 is an acceptable solution but not the "best".

This backpressure problem has only recently come to the attention of the SPCR-wide audience, probably due to the abject failure of the expensive and heralded low-noise 7-blade Noctua fan to handle even reasonable amounts of backpressure.

The only way to reduce backpressure in your situation is not to use closely spaced fins on your HS... bye bye U120, hello Ninja!

FYI, the best fan to use on a Ninja is a Scythe Slipstream.

[Tzupy]

@Felger Carbon: Do you mean that the S-Flex isn't so good for tightly spaced heatsinks?
I remember reading in this forum section a comparison of fans versus backpressure, and the S-Flex came best.
I don't remember who wrote that post (sorry), but it was either you or Bluefront.
When talking about the Noctua you mean the old 7-blade fan. The new 9-blade Noctua NF-P12 seems to handle backpressure well.
Link to Xbitlabs review: http://www.xbitlabs.com/articles/cooler ... undup.html
Unfortunately the NF-P12's rpm varies only between 800-1300: http://www.xbitlabs.com/articles/cooler ... html#sect0

[Felger Carbon]

@Felger Carbon: Do you mean that the S-Flex isn't so good for tightly spaced heatsinks?

Code: Select all

from an earlier posting, repeated as reference:
YL SM 1041RPM 560prop 48.2dBA
GW NCB 970RPM 560prop 44.9dBA (NCB sample #2)
SC PWM 910RPM 560prop 48.6dBA Kama PWM 100%
AC PWM 902RPM 560prop 46.1dBA Arctic Cooling PWM 100%
UC12EB 880RPM 560prop 41.2dBA (a sweet-sounding fan)
SilenX 866RPM 560prop 45.4dBA "11dBA" version
SFlexE 852RPM 560prop 42.3dBA (quieter than NCB!)
9blade 686RPM 560prop 39.6dBA Scythe SlipStream

Above are some 120mm fan measurements at equal airflow, as indicated by 560RPM on the airflow sensor prop. Of all those fans, the SFlex needs fewer RPMs than any 7-blade prop, meaning it has a higher pitch than all the other 7-blade fans. The Yate Loon (aka Nexus) and GW NCB have the lowest pitch and so should be better in high impedance situations. Madshrimps has adopted the GW NCB fan as their standard fan for testing HSFs that use 120mm fans.

I can assure you that I am not the person who allegedly claimed the SFlex was good for high-pressure situations.

When talking about the Noctua you mean the old 7-blade fan.

Yes, I specifically mentioned "7 blades".

[JaYp146]

@Felger Carbon: Do you mean that the S-Flex isn't so good for tightly spaced heatsinks?

Code: Select all

from an earlier posting, repeated as reference:
YL SM 1041RPM 560prop 48.2dBA
GW NCB 970RPM 560prop 44.9dBA (NCB sample #2)
SC PWM 910RPM 560prop 48.6dBA Kama PWM 100%
AC PWM 902RPM 560prop 46.1dBA Arctic Cooling PWM 100%
UC12EB 880RPM 560prop 41.2dBA (a sweet-sounding fan)
SilenX 866RPM 560prop 45.4dBA "11dBA" version
SFlexE 852RPM 560prop 42.3dBA (quieter than NCB!)
9blade 686RPM 560prop 39.6dBA Scythe SlipStream

Above are some 120mm fan measurements at equal airflow, as indicated by 560RPM on the airflow sensor prop. Of all those fans, the SFlex needs fewer RPMs than any 7-blade prop, meaning it has a higher pitch than all the other 7-blade fans. The Yate Loon (aka Nexus) and GW NCB have the lowest pitch and so should be better in high impedance situations. Madshrimps has adopted the GW NCB fan as their standard fan for testing HSFs that use 120mm fans.

I can assure you that I am not the person who allegedly claimed the SFlex was good for high-pressure situations.

When talking about the Noctua you mean the old 7-blade fan.

Yes, I specifically mentioned "7 blades".

So out of those, which would you recommend to be the best 120mm fan for heatsinks with tightly spaced fins? The Yate and GW NCB? Kinda confused as to what you meant.

And not to thread hijack, but which would you recommend for the Xigmatek HDT-S1283 (AKA Kingwin Revolution)?

Thanks in advance ...

[Felger Carbon]

So out of those, which would you recommend to be the best 120mm fan for heatsinks with tightly spaced fins? The Yate and GW NCB?
And not to thread hijack, but which would you recommend for the Xigmatek HDT-S1283 (AKA Kingwin Revolution)?

Personally, I'd use the GW NCB with a U120. I think YL's time has passed.

I'm unfamiliar with the fin thickness and spacing (both get into the backpressure act) on the Xigma, so I have no basis for a recommendation. While I see lotsa recommendations for the HS, I see a whole lot fewer comments about replacing the provided fan. Give it a try - it's free with the HS, after all!

[jaganath]

Personally, I'd use the GW NCB with a U120. I think YL's time has passed.

I shall mourn the passing of the YL's. quiet performance to rival the Nexii and Slipstreams of this world, but at bargain basement prices. also, the NCB doesn't seem to be available outside of NA, so YL bestrides Europe like a colossus.

[Tzupy]

I found the thread, it was Bluefront's, and his conclusion, quoting: 'I'm still saying the 1600 S-Flex is your best bet in a setup with restriction and filters'.
Link to thread: viewtopic.php?t=45788&highlight=scythe+ ... 11d800494c
@Felger Carbon: I'm confused, the results you have seem to contradict Bluefront's results. I don't dispute either results, I just want a clear conclusion.

[NeilBlanchard]

Hello,

I don't think the Xigmatek qualifies as having very tightly spaced fins -- not like the Thermalright U120, anyway. I don't think it rises to the level of a filter on a positively pressurized case; probably not even close!

The GlobalWin NCB fan has broad blades that are at low pitch (both of which would help in higher pressure situations) -- but it has a wide gap at the ends of the blades (which is a negative).

The Slipstreams have 9 curved blades (which good), but they are relatively narrow and are more steeply pitched (which is no-so-good).

The S-Flex is probably better in higher pressure situations, but I don't know if the Xigmatek means that all of these other quiet fans won't also work.

[Felger Carbon]

@Felger Carbon: I'm confused, the results you have seem to contradict Bluefront's results. I don't dispute either results, I just want a clear conclusion.

The obvious and clear conclusion is that Bluefront and I are independent. We agree on lots of things and disagree on some. Bluefront always uses filters; I never use filters (as an example).

SPCR has lotsa opinionated members. Unanimity will not be found at SPCR!

[Felger Carbon]

...the NCB doesn't seem to be available outside of NA...

In the Scandinavian countries, the NCB is available under different marques. Who cares whether a fogbound island or three off the coast of France has them available across the counter?

[Aris]

I use 120mm 1200rpm scythe s-flex's all around for every system. If i need a 92mm fan, i use nexus. Most fans i have in any system is 3, but usually 2. And you can hook all of them up to a single Fanmate. I have one in every system i build. I usually have it set to 6v, which is 600rpm on the sflex's. You wont be able to hear them from outside the case with case panels on.

Just make sure you use effecient heatsinks so low airflow wont be an issue. I personally like thermalright for both CPU and GPU. They may charge a bit of a premium, but they are IMO the best in the buisness.

[thejamppa]

...the NCB doesn't seem to be available outside of NA...

In the Scandinavian countries, the NCB is available under different marques. Who cares whether a fogbound island or three off the coast of France has them available across the counter?

In here, near the Arctic Circle the NCB fan are under name Liebermann... which now has also 60mm Psi-Blade with NCB bearings.

[bgavin]

The S1283 uses fin dimensions of 0.35mm thick, and 1.75mm spacing. In 2D square area (no depth), I figure open air percentage at 81.8%. This compares with 75.0% for the Ultra 90, 76.2% for the TRUE, and 90.4% for the Ninja Mini.

[nervx]

tried some different configs today.

thermalright results:
s-flex 1200rpm - annoying buzz/whistle (sounds like a faint boiling kettle)
s-flex 800rpm with fanmate - quiet
nexus - slightly more noise than the s-flex at 800rpm but not by much

rear 120mm cooling fan results:
s-flex 1200rpm - annoying buzz/whistle occurs here as well
s-flex 800rpm - still a bit noisy but not bad
nexus - slightly quieter than the s-flex at 800 but also has a bit of the buzz/whistle
tri-cool on low - no buzz/whistle but more airflow noise.

im going to cut the grill off the back of the case to reduce noise from impedance but is it possible to use a fanmate with the tri-cool fans and if so what should i set the 3 speed thing at when doing so?

for the thermalright im thinking of buying a second fanmate and running it at 800rpm. the cfm is very close to the nexus at this speed but the pressure should be a bit better correct?