Question CPU fan strange behaviour (start/stop) and CPU fan error

[ppg20]

Hi, out of nowhere my Cooler Master Hyper 212 rgb fan on TUF x570 plus mobo started doing this: Right after start, it goes into a start/stop mode where it switches between running and complete stops. Someties I get a CPU error screen on startup with only option is going into BIOS, then when I exit BIOS without changing anything, or just restart manually from the screen, sometimes it goes back to the error screen, sometimes I'm able to start Windows normally. Once in Windows, the start/stop continues, but when I tried to put some load on the CPU which got it to warm up, the CPU fan seemed to follow the temperature and work normally. Once the load was off, it went right back to start/stop.
One more thing: I tried to switch the cables to a different dedicated header on the mobo. Normally it's in CPU_FAN and the RGB cable is in the RGB header right next to it (the fit on the RGB cable isn't great, it feels like it's not "locking" really, but it always worked as intended). When I put the cable in CPU_OPT (optional) and leave the RGB cable unplugged, the fan is constantly on 100 % RPM (I assume), it doesn't show up in HW Monitor. It also sometimes goes to the error screen on startup, sometimes not. BUT when I have the cable in either header AND the RGB cable is plugged in, the CPU fan always goes into the start/stop mode. Bizzare. When I plugged the fan into a different header (chassis fan) it did'nt fix the problem (still start/stop)

Any suggestions anyone? Could it be a power issue? Or the fan is just broken? I also tried 2 RAM sticks instead of 4. Thx for help.

 

[ppg20]

Little update: When I have the fan connected to the CPU_OPT header, I'm able to skip the error screen on the startup only if I put the fan to "full" setting in BIOS (it always goes 100 %). Otherwise it just doesn't "pass the check" on startup.

 

[Vic 40]

This only happens with the rgb cable connected? Tested on the other rgb header as well? Rgb connector the right way on the header?

 

[DRagor]

Typically such behavior is caused by setting too low fan speed at low temps. Now I understand it worked fine on same settings before, but as fan ages the increased friction on bearing could cause this even on same settings. So the first thing to do is to go to BIOS and change the fan curve at low speeds. If the fan is otherwise fine it should solve your problem. If not it could mean the fan itself is faulty. In such case I would take some other fan and put it onto 212 heasink and see if that solves the problem.

 

[ppg20]

I tried a different fan at the same headers and the CPU fan in different headers. All worked fine. I've put it back in place and now seems to work fine now. I don't know, maybe there was a bad contact between the cables and the fan itself, maybe there was some problem with the stupid Amory Crate program (Asus all-under-one-roof bloatware) that I've updated. Will see what happens when it sits over night.

It might be just a physicall friction in the ball bearings, as suggested, that gets better when I fuss with the thing trying it out, we will see.

 

[Vic 40]

Will see what happens when it sits over night.

okay

 

[ppg20]

Update

This is what I thought:

Ok, so after some further testing, I think the rgb header is the problem. I had the fan working perfectly normal, with rgb, but as soon as I went to Aura Creator through Armory Crate to change the color on the adressable rbg thing is my PC, the start/stop came again. I exited the program, the fan worked ok again. I tried that few times and then the start/stop became permanent. I want to point out that the problem came back the very second I clicked on the color setting, repeatedly. Even started to get the startup error again, but this time the fan wouldn't change to "full speed" mode in bios if selected. So I unplugged the rgb cable and on the next start it again worked normally.

BUT

As I am writing this, the fan is without rgb plugged it, but unfortunately the problem appeared again few times, then it was ok, then again. Was running normally for few minutes, then stopped again. So I'm at a loss again.

 

[DRagor]

So in the end nothing has changed. I would swap the fan at this point.

 

[ppg20]

So in the end nothing has changed. I would swap the fan at this point.

Yeah, well that is always the option I know, but it's the strange connection between the software and the problem, that's so weird... Why would an rgb adressing program affect a function of a fan when changing the color of the leds? Or how would rgb lighting on a fan affect it's function at all? It doesn't seem to me there's a connection, other then maybe short-circuiting something in the fan or on the mobo? I'm just trying to get more info on if that's even possible.

 

[DRagor]

Or how would rgb lighting on a fan affect it's function at all?

There should be no connection. Motor and lights are on two separate circuits. At least should be. Maybe you are right about a short of some kind inside fan.