Noisy case fan on Antec SLK-1650B

[BernardP]

I just got a new system with an Antec SLK-1650B case/PS. The rear case fan is louder than I expected from reading positive reviews on NewEgg, where many people are praising the case fan's quietness. The case fan's noise is drowning the CPU fan and the PS fan.

This case fan has only one speed, which seems to be quite high. The system is not self-built, but was put together by a local shop. Contrary to what is said in the Antec manual, the fan is not connected with a 4-pin molex. There are only a black and a red wire coming from the fan motor, and theses wires are rigged to the black and red pins of a molex coming from the PS. From this article, I understand that the case fan should only be getting 5 volts, so it should run slower and quieter. But it does not...

I don't even know if a Zalman Fan Mate would fit with my case fan. The Fan Mate has a 4-pin molex connector, but my case fan doesn't: only black and red wires.

Of course I could try to buy a new fan, but I would first like to find what, with the current setup, could be the cause of the excessive noise.

Thanks for your comments and suggestions

 

[zagood]

First of all, open up your case and, while running, stick your finger on the center of the fan to slow it down and see if that changes the sound of the case. Do this with all other fans as well.

The two wire connection that you see terminates in a 3-pin fan header. The FanMate (both 1 and 2) uses a 3-pin connection, not 4-pin. Should be fine.

I'd recommend a different fan though. Do some searching on this forum and you'll see tons of suggestions for 120mm fans.

-z

 

[anandtechrocks]

I've got the same case, and yes that fan is way too loud. I bought a fan controller and brought it down to 1400 RPM and it is quiet now.

 

[BernardP]

Thanks zagood, I'll check this, but it has to wait until tomorrow.

The back and red wires from the fan end up buried in the white plastic at the base of a 4-pin molex. Looks like a strange connection to me. No 3-pin connection can be seen.

anandtechrocks...So I am not alone...

What was the RPM before you brought it down?

Could you tell me what fan controller you bought?

 

[Madwand1]

Originally posted by: BernardP
Contrary to what is said in the Antec manual, the fan is not connected with a 4-pin molex. There are only a black and a red wire coming from the fan motor, and theses wires are rigged to the black and red pins of a molex coming from the PS.

In my 1650B, there are two wires from the fan leading to a 4-pin molex connector / pass-through adapter.

I understand that the case fan should only be getting 5 volts, so it should run slower and quieter. But it does not...

The typical red-black colouring in case fans can be confusing with the standard yellow-black colouring for PSU 12V cables. However, these, like almost all case fans, are 12V, and if you look more carefully, you should see them connecting to the yellow/black wires from the PSU.

This also means that you can try the 5V trick; switching the pins on an adapter. It'll certainly be a lot quieter; whether or not it will give enough airflow depends...

I don't even know if a Zalman Fan Mate would fit with my case fan. The Fan Mate has a 4-pin molex connector, but my case fan doesn't: only black and red wires.

The Fanmate has "the other standard" 3-pin fan connector only. It would not connect to this fan unless you have a molex to 3-pin adapter.

Unless you simply snip the wires and splice them. I suggest doing this, unless you feel potential need for a more complex controller.

Of course I could try to buy a new fan, but I would first like to find what, with the current setup, could be the cause of the excessive noise.

That fan moves a lot of air, much more than many current cases with 120mm fans. It's not so much that most people would strongly object, and is probably quieter than many 80mm fan setups (perhaps that's why Newegg reviews claimed it was quiet). On that -- I assume your vendor has not thrown in a (typically loud) 80mm fan in the intake; if so, it could also be a culprit. However, the Antec 120 is certainly not in the "silent" category.

The quickest solution will probably be to get a quieter case fan -- an Antec Tri-cool for example would let you try different volumes.

A controller, e.g. the Sunbeam Rhobeus, will let you balance the airflow / noise more finely, and could also be useful for the front intake and side intake should you decide to include (typically noisier) smaller fans there. The Sunbeam comes with two molex to 3-pin adapters. Other controllers come with fancier (read: even brighter and flashier) displays with more functionality (RPM, temperature, alarms).

Also consider blocking the side intake. Once you get the rear fan quieter, you might notice the sound coming out of the side. Putting in an ad hoc filter here can make it quieter and also reduce the dust intake, though at some reduction in CPU cooling. However, as a general rule, if you're going to quite/slow fans, you want to remove obstacles so that the little airflow they generate is maximized.

 

[BernardP]

Thanks for the thorough explanation Madwand1,

There are a couple of 120 mm Antec Tricool fans that seem to fit the bill if I have to get a new fan.

What puzzles me for now is the way the black/red wire from the fan is "merged" in the base of a 4-pin molex. There seems to be a small flap/door on the white plastic at the base of the molex, but I don't know if I risk breaking something if I pull on this. Is there a connector under this flap, or has the tech who put the computer together jury-rigged a connection?

Also, I notice that only this particular 4-pin molex has the little flap.

I have no doubts that experts in the matter must find my doubts amusing, to say the least 😱
As a beginner in this kind of things, I want to be extra-cautious. As my wife says in regard to sewing: "Measure three times, cut once"

Thanks for your support.

 

[Madwand1]

Oh yeah, I just noticed the flap in my fan too. I tried yanking on it a bit, but it didn't budge. Then I decided to get persuasive, and used a small screwdriver to pry it open at the pins. That opened it, but I couldn't see anything else to do with it, and didn't quite get the point of it. Perhaps it helps in assembly and allows the fan wires to be in a convenient spot. There's no connector that we can use inside, so it's got no real relevance to us here.

The entire plug itself should be disconnected from the other cable that it's connected to, when removing the fan. The plug, like many molex fan / etc. connectors, has one side for connecting to the power supply, and another side for connecting a second device. That way, the fan gets power, but don't take up one of the limited power supply cords. Convenient.

To disconnect the fan, simply remove the fan plug from the chain, and if anything was connected to the fan cord behind it, connect that directly to the PSU cable.

You should be able find a molex to 3-pin adapter in stores if you want to go the Fanmate route. If not, you could simply cut and splice the wires. Alternatively, just replace the fan.

 

[BernardP]

Thanks again Madwand1

With your explanation, I had another look at the fan connection and now I understand. Even if the fan wires are black/red, they are connected to the yellow/black leads on the PSU side, hence 12 volts. I was under the impression that there was some kind of non-standard connection behind the little flap. I had not realized that the white part of the connector is on the fan wire side, not on the PSU side.

So, I have 2 choices: Cutting and splicing some wires to see what 5-volting the fan would do, or getting a Tricool fan. I am leaning towards the latter.