Best 80mm fan?

[Ricemarine]

Well, I am looking for those 45-60 cfm fans that don't carry more than 45 dba, so I am asking for you guys to recommend some fans for me.... I have thought of these choices, if you like em, please tell me...

53cfm/39 dba Mechatronics
50cfm/40 dba Sunon High Output
53cfm/46 dba Aerocool X-Blaster
47cfm/47 dba Panasonic UH1

 

[Zucarita9000]

Hmm... I haven't had too much experience with fans, just some generic ones, some Antecs and some Panaflos. I use 120s since both my computers have 120mm intake/outake fans.

I'm using two Panaflo 120L1As in my system. These babies can move air! (about 70CFMs) and are pretty quiet.

Lots of people here comment that the 80mm Panaflos are some of the best fans you can find. My 120s are not bad either.

I've heard good thing about Sunon also.

FYE: Don't follow manufacturers specs to the letter. Sometimes, 40dBa may seem good but no one says if the sound they produce is a high-pitched one or a low-pitched one. It's -obviously- more pleasent to have a low-pitched "hum" that a high-pitched, irritatting whining (not sure if spelled correctly).

My Panaflos produce a low-pitched hum, wich is produced by air turbulence. Does not appear to be vibration noise.

Be aware that high speed 80mm fans can produce vibration if not installed with some kind of dampening system, such as rubber grommets, etc. This will add to the overall noise level.

 

[Navid]

CFM is a linear unit. dBa is a logarithmic unit.
Dividing one by the other can be misleading.

In other words, if you double the CFM of a fan, you are doubling the amount of air it moves. But, if you double the dBa of a 40dBa fan, you had better have earplugs! That is not just doubling the noise

 

[akira34]

Originally posted by: Navid
CFM is a linear unit. dBa is a logarithmic unit.
Dividing one by the other can be misleading.

In other words, if you double the CFM of a fan, you are doubling the amount of air it moves. But, if you double the dBa of a 40dBa fan, you had better have earplugs! That is not just doubling the noise

Each 10 point increase in dbA makes for twice as loud... So, a 30dbA item is twice as loud as a 20dbA item... 30 to 40 is another 2x factor (on top of the 30dbA sound level).

 

[Spike]

Originally posted by: Ricemarine
Well, I am looking for those 45-60 cfm fans that don't carry more than 45 dba, so I am asking for you guys to recommend some fans for me.... I have thought of these choices, if you like em, please tell me...

53cfm/39 dba Mechatronics
50cfm/40 dba Sunon High Output
53cfm/46 dba Aerocool X-Blaster
47cfm/47 dba Panasonic UH1

Personally I think all those are unacceptable. I have a YS-Tech 80mm rated at 48 CFM @ 38dB and that baby is pretty loud at the full 12v. In order to make it acceptable, I run it at 8-9v and it is quieter, though it is by far the loudest thing in my case (on my CPU).

I would look at the Panaflo 80mm H1A and M1A as well as offerings from YS-Tech and Enermax. You can find quieter fans that push about the same amount of air though that Mechtronics sounds ok if it's specs can be believed.

-spike

 

[CraigRT]

heh, those are some loud fans...
i like like 20 dba noise level

 

[Spike]

Originally posted by: akira34

Originally posted by: Navid
CFM is a linear unit. dBa is a logarithmic unit.
Dividing one by the other can be misleading.

In other words, if you double the CFM of a fan, you are doubling the amount of air it moves. But, if you double the dBa of a 40dBa fan, you had better have earplugs! That is not just doubling the noise

Each 10 point increase in dbA makes for twice as loud... So, a 30dbA item is twice as loud as a 20dbA item... 30 to 40 is another 2x factor (on top of the 30dbA sound level).

Actually each 3 dB is a doubling of sound and each 10dB you go up you have 10x the sound. ie 40db is 10x louder than 30db.

Decibel explanation

 

[Operandi]

Originally posted by: Spike

Originally posted by: akira34

Originally posted by: Navid
CFM is a linear unit. dBa is a logarithmic unit.
Dividing one by the other can be misleading.

In other words, if you double the CFM of a fan, you are doubling the amount of air it moves. But, if you double the dBa of a 40dBa fan, you had better have earplugs! That is not just doubling the noise

Each 10 point increase in dbA makes for twice as loud... So, a 30dbA item is twice as loud as a 20dbA item... 30 to 40 is another 2x factor (on top of the 30dbA sound level).

Actually each 3 dB is a doubling of sound and each 10dB you go up you have 10x the sound. ie 40db is 10x louder than 30db.

Decibel explanation

No, a 10 dBA increase is perceived by the ear as twice as loud, not 3. If you add another source, in this case an identical fan you have a 3dBA increase in the noise level. Example 2 20 dBA fans would come in at 23dBA.

 

[Spike]

Googleing found this:

Link 1
quote: "On the decibel scale, the smallest audible sound (near total silence) is 0 dB. A sound 10 times more powerful is 10 dB"

Link 2
Language in Link 2 is "twice as much power" for a 3dB increase

Link 3
"In other words, a sound that is twice as loud as another sound could be described as being 10 decibels (10 dB) louder." Does this mean that twice as powerful and twice as loud are two different things?

Link 4
Again, they say here 10dB is twice as loud to the human ear but 10 times more powerful....

I guess 10db is twice as "loud" but 3dB is twice as "powerful", whatever that means

-spike

 

[Navid]

Logarithm of 1 is 0.
Logarithm of 10 is 1.
Logarithm of 100 is 2.
Logarithm of 1000 is 3.
.
.
.

This is the decimal Logarithm.
If you have a calculator with scientific setting, you can check these out. So, the Logarithm of 5 is between 0 and 1.


dB is calculated as 20Log of the value for amplitude and 10Log of the value for power.

The difference between power and amplitude is easier to talk about in electrical engineering.
Amplitude is the peak voltage across the load. Power delivered to the load is voltage across the load multiplied by the current through the load. If you double the voltage across a resistor, you will also double the current through it. So, the power delivered to the resistor will be multiplied by 4 (2V X 2I = 4 VI).

Logarithm of 2 is 0.30102999999. So doubling the voltage in dB is 20 X Log 2 = 20 X 0.301 = 6dB.

Doubling the power in dB is 10 X Log 2 = 10 X 0.301 = 3dB.

3dB and 6dB are numbers that many use when talking in dB because of the relationship with doubling.

Multiplying by 10 is another thing that people talk about in dB.
Log of 10, as I said, is 1.
So, multiplying the amplitude by 10, in dB, is 20 X Log 10 = 20 X 1 = 20dB.
Multiplying power by 10, in dB, is 10 X Log 10 = 10 X 1 = 10dB.

Edit: Spelling

 

[Spike]

Thanks for that! I wish I had actually paid attention in my EE classes now...

-spike

 

[xbassman]

Originally posted by: Ricemarine
Well, I am looking for those 45-60 cfm fans that don't carry more than 45 dba, so I am asking for you guys to recommend some fans for me.... I have thought of these choices, if you like em, please tell me...

53cfm/39 dba Mechatronics
50cfm/40 dba Sunon High Output
53cfm/46 dba Aerocool X-Blaster
47cfm/47 dba Panasonic UH1

These are for a heatsink I hope!

Actually I have used both the Panaflo and the Sunon.
The Panaflo is quieter than the Sunon despite the specs. It can be a little loud @12V. It runs a lot quieter @ 7V. (I am using them as heatsink/fans on a few boxes here.)
The Sunons were just too loud for me.

 

[Ricemarine]

O..k... I get to learn more about dBA! yay. Fine, let's put it this way, if you can't remove any of the fans, and 6 were intake, 3 were exhaust... What would you do... YOU CAN'T REMOVE ANY FANS, ONLY REPLACE

5 fans are in front of the hard drive for intake (4 are 32 cfm, Coolermaster, 1 is speeze, 28 cfm)
1 fan intake on the side (about 20-25 cfm)
2 exhaust fans rear(20 cfm each)
1 exhaust fan top (20 cfm)

My heatsink is 48.5 dba, which is really loud, so I wouldn't really mind anything about 5 dba less.

 

[xbassman]

Wow! Can't remove them huh?
Are you having heat issues or silent issues?

 

[Tiamat]

I keep repeating myself. Having 6 intake and 3 exhaust is the main cause for your heat problems.

Lets go to a simple balance: in + generation - out - accumulation = 0. Set the control volume as your computer case. Since there is no chemical reaction, air is not generated or created within your case. So, you are left with the following equation: in - out = accumulation. In an ideal case, you have 181 cubic feet per minute flowing into your control volume. 60 of which are allowed to flow out. Therefore in your control volume, you have an accumulation of 121 cubic feet each minute. So, by minute two, you have 242 cubic feet of heated air stuck in your computer case minus the amount that get released from the cracks of the computer case.

In order to fix this system, you will need to a.) get rid of 3 intake fans b.) put a 120x38mm Delta Ultra high RPM fan as exhaust.

In conclusion, your CPU heatsink is not at fault, nor is the fan on it. Your cpu fan is simply using the warm air that it is recycling due to the net accumulation of heated air of 121 cfm in your case.

Once you have taken one of these moves and if you still have problems report back, otherwise, we will be sounding like a broken record.

Edit: In other words: unless you fix your airflow balance, no cpu heatsink/fan options will make a difference.

 

[Spike]

Originally posted by: Ricemarine
O..k... I get to learn more about dBA! yay. Fine, let's put it this way, if you can't remove any of the fans, and 6 were intake, 3 were exhaust... What would you do... YOU CAN'T REMOVE ANY FANS, ONLY REPLACE

5 fans are in front of the hard drive for intake (4 are 32 cfm, Coolermaster, 1 is speeze, 28 cfm)
1 fan intake on the side (about 20-25 cfm)
2 exhaust fans rear(20 cfm each)
1 exhaust fan top (20 cfm)

My heatsink is 48.5 dba, which is really loud, so I wouldn't really mind anything about 5 dba less.

If you can't remove any fans and I have to have 9 total, here would be my solution:

replace 3 intake with 3 Panaflo M1A intake,
replace 3 intake with 3 broken or not plugged in intake fans (no rotation)
replace 3 exhaust with 3 Panaflo M1A exhaust.

3+3+3 = 9 fans, yes!

-Spike

 

[Gamingphreek]

I agree with Tiamat.

There is ABSOLUTELY no need for more than 5 case fans (assuming 80mm, if larger 3 max). Anymore creates a sort of vacuum which starves your CPU fan of air. I have a 5ht fan in my computer on the door, which i leave unplugged. It makes no difference whatsoever. On top of that your system is allready not of equal pressure ie too much air going in and not enoguh getting spit back out.

The threee best quiet fan makers are:
Acoustifan, Panaflo, and Nexus.
For high speed:
Delta and Vantec are very nice but noisy.

-Kevin

 

[Ricemarine]

LOL... Spikes idea actually got to me

Btw, noise is not really an issue unless its over 50 dba

So tell me if my idea works...
Get two mechatronics fans (53cfm, recommended by many if they've heard of it) 106 cfm-20cfm for replacing 2 fans = 66 cfm
1 exhaust blower = 42cfm (some kind)
42 + 66 cfm = 108 cfm
116 - 108 cfm = 8 cfm intake vs exhaust difference. Bad or good?

If we plug it in exhaust vs intake
176 cfm = intake
53 X 2 = 106 + 42 = 148 cfm
176 - 148 cfm = 28 cfm

Oh wow, aight, that means, I need to add an H1A lol, should I add that too? That would even it out pretty much.

 

[Gamingphreek]

What are you having trouble comprehending. Get rid of all of those fans!! THey are doing nothing but causing noise and problems.

Get 4 case fans (5 if you have one in the top of your case). Any more is a waste, as it does nothing but create a kind of vacuum, increases noise, dust, and electricty.

If you want a cool system and dont care at all about noise than just get 4 Vantec Tornados. Or to be more efficient get 4 H1A's.

-Kevin

 

[Ricemarine]

No... I do understand, that's why I unplugged a few of my fans

 

[IlllI]

9 DOES seem pretty excessive