Fan running at lower RPM when the case is straight

[alex223]

I just bought my first AIO and i have a lot of issue with my fan. I have my AIO at the top of my case here is my question, is it normal for a fan to run at a lower RPM than normal when the case is straight, and run at a higher RPM (100/300RPM more) when the case is inclined . *Temps doesn't change and fan are running at full speed*

1800-1900 RPM Case straight
2000-2200 RPM Case inclined

Here's my AIO : Lepa AquaChanger 240

The answer is probably no but i just want to be sure before requesting a refund.

 

[EarthDog]

Maybe...less friction in the bearings.. something. That said, rpm readings arent terribly accurate either and float 100rpm or so.

But uhh, what do you mean inclined? How much incline? Doesnt really change my answer though.

 

[alex223]

Thanks for the reply

You can also hear and feel the difference, it's not only the RPM reading that are changing.

By straight i mean oriented vertically and by inclined i mean slightly inclined(not "straight" and not laying flat, somewhere in between)

 

[Mr.Scott]

It's a cheap fan.
They all do that.
Do you actually use your rig tilted?

 

[alex223]

Oh.

No i don't, i just noticed it when i was testing my aio to try to fix some other issue.

 

[trents]

Has to be something to do with the stress vector changing on the bearings. Do you know what kind of bearings are in the fans? Sleeve? Ball bearing? Fluid?

 

[alex223]

No idea at all,

New problems both fan start to slow down for no reason, when they are supposed to run at max they are slowly reducing their speed. ~400-800RPM less. whch cause the cpu to heat too much.

Damn this AIO is terrible.

Edit : This is happening while gaming/stress testing

 

[trents]

How are the fans controlled? Are they PWM (four wire) fans that connect directly to the motherboard? Three wire constant speed (supposedly) connected to the motherboard or do they plug into the pump and are controlled by signals from the pump? Are all the fans on the radiator slowing down in unison? Do you notice case fans also slowing down?

 

[alex223]

How are the fans controlled?

I'm controlling my fan using speedfan(I'm going to try to un-install speedfan and use the motherboard software) Edit :While i was in the bios i had the same problems with my fan so it can't be speedfan doing it since it wasn't open.

Are they PWM (four wire) fans that connect directly to the motherboard? Three wire constant speed (supposedly) connected to the motherboard or do they plug into the pump and are controlled by signals from the pump?

Yes all my fan are PWN connected to all my case fan 4-pin connector. My pump(3-pin) is connected to my CPU fan pin(Power mode for this "fan" is set as turbo in the bios)

Are all the fans on the radiator slowing down in unison?

They are all slowing down one is slowing down a bit faster than the other (Picture while stress testing both fan at 100%, max RPM of these fan are supposed to be at 2300RPM)

Do you notice case fans also slowing down?

The pump and my only case fan are not slowing down at all

Thank you for the help i really appreciate that.

Additionnal info: i was gaming /w my fan at a stable 65% and stable temps then i tried to put my fan at 100% They only gained 50-100RPM(from 1500 to 1600) then they started slowing down again

 

[trents]

Is the one case fan a three wire or a four wire fan? Does the header the pump is connected to have three pins or four pins?

Since the pump only has three wires and is connected to a case fan motherboard header it is not likely going to be controlled by the speed setting in bios. It will run full bore no matter what setting in bios you apply to that header. I have seen motherboards that controlled rotating connected devices like fans and pumps using voltage reduction but haven't seen one for several years. It's not a good way of controlling rpm since the impedance (resistance to initial start up) of the device being controlled really limits how far you can reduce RPM. That's why PWM (Pusle Width Modulation) has become so popular. It controls the speed maintaining a constant voltage but breaking the flow of electricity into pulses whose duration can be adjusted. This offsets the impedance problem somewhat and allows for considerably more speed reduction than does voltage control. The fourth wire on a four wire PWM device is the modulation wire.

 

[alex223]

Is the one case fan a three wire or a four wire fan?

It's a four wire fan like my water cooling fan.

Does the header the pump is connected to have three pins or four pins?

I only have 4-pin on my motherboard but my pump have a 3-pin connector

Ok i'm 99% sure that it's a technical problem, i uninstalled speedfan and installed the motherboard software to control the fan. There was no difference. So i tried something, i put my case on it side and run my fan at 100% like i did before. Right now they are not slowing down anymore.

 

[trents]

Well a three wire pump connected to a four pin header will not allow you to control the speed of the pump.

A "technical problem"? What do you mean by that? Setting is wrong? Hardware issue? Software issue?


"Right now they are no slowing down anymore." So is the problem fixed?

 

[EarthDog]

SOME mobos allow for both PWM and voltage control on the same header, note... not sure if his does, but I have seen a few..

This is typically on higher end mobos. Not sure what the OP has.

 

[demien88]

If I were you I would play around with molex adapters. If the fans are not broken they should run full speed when connected to it. Had similar issue but my problem was that I plugged fan into header that lets you control speed which I had no idea how to do under bios it was bit confusing. It always ran at 800 rpm instead of 1300.
Try to test fans I have feeling they are failing for some reason, also uninstal all fan controlling software.

 

[alex223]

Well a three wire pump connected to a four pin header will not allow you to control the speed of the pump.

Oh yea i forgot about that

A "technical problem"? What do you mean by that? Setting is wrong? Hardware issue? Software issue?


"Right now they are no slowing down anymore." So is the problem fixed?

I mean hardware problem those fan are probably broken or bad quality. The problem is not really fixed since my case need to be on it side to get good cooling but it's ok

This is typically on higher end mobos. Not sure what the OP has.

I have a ASUS M5A97 R2.0


Thank you all for your help!