[SOLVED] How to turn off RGB LEDs of non-addressable fan ?

[donutcoffee]

I bought some CP3 LED 120mm case fans on Amazon. At first I thought I would like them. Now they're just driving me absolutely nuts.

They're so damn bright. They're almost as bright as my desk lap, except in RGB colors. I literally have trouble sleeping from the piercing blue light that emanates from these case fans. I've tried to disassemble them but there are no screws at all. It seems like the case of the fan is just a pure hunk of plastic and there's no way to get into it.

Anyone have any ideas about how to turn this darn light off? I am using a molex 4 pin connector since the motherboard 3 pin connectors don't provide enough voltage (?) to the fans. When I plug them into the motherboard header, only half the LEDs turn on at 20% of the typical brightness (great!) but the fans run extremely slowly as well (not so great). Perhaps worst case scenario I can reach in with a knife and try to mess up the LEDs on the inside?

This is the front and side of the fan. As you can tell, absolutely no screws to open it and remove/disconnect the LEDs

 

[Ralston18]

First: stay out of the PC with a knife.....

Second: How did you make the current connections?

From the link you provided:

"【Easy to Install】 Easy to install and compatible with all types of cases; straightforward power supply interface design with small 3-pin on the mother and 4-pin for the power supply; Please do not connect both 3-pin and 4-pin at the same time to avoid short circuit; (Notice: this model does not have ARGB function and there is no remote control or controller. Please do not connect them to the controller.) "

The most straightforward solution is to remove the current RGB/LED fans and replace them with another fan product that meets your requirements. Consider foregoing RGB altogether.

Return (RMA) the current, too bright, fans.

 

[donutcoffee]

First: stay out of the PC with a knife.....

Sorry, what does that mean?

I am using a molex 4 pin connector which is connected directly to my power supply. I was hoping maybe there was one pin that I could "block" which would turn off the rgb altogether

 

[Karadjgne]

The rated amperage on those fans can total only 0.6A, so should be plenty coming from a motherboard header.

But they are a 3pin fan with integrated 12v lighting. What that means is they are Voltage controlled. When hooked to the motherboard, the motherboard sends a 7v-12v signal to the fan to determine its speeds. The faster the fan, the higher the voltage required, the brighter the light.

By connecting to molex, you immediately/permanently give the fan 12v, so it's always at max brightness and max speeds.

The only way to disable the lighting, is permanently unless you are good with soldering and wiring. In the back of the fan there will be visible a very small wire that circumnavigates the surround, that's the led wiring. Snip that wire, and lights go out. Add a switch between those snipped ends and you can turn the lights ob/off.

The fans are a lie. They are not RGB in the normal sense, they are LED with several color led filaments, you cannot change the colors since the voltage/amperage is supplied by the fan itself.

I'd return the fans, get a simple non-led/rgb 3pack of corsair or fractal design fans etc.

 

[Ralston18]

Knife - from your Original Post:

"Perhaps worst case scenario I can reach in with a knife and try to mess up the LEDs on the inside? "

Poking about in electronics with a knife even with the best of intentions and greatest care is likely to end badly one way or another.

So what my comment meant/means is "Do not do that".

@Karadjgne 's post is much more the gist of it all. I will defer to his suggestions.

 

[Karadjgne]

Knife...

That's asking a Diesel mechanic to break out his tool box, to remove a splinter ...

As I see it, being voltage controlled, the fan is going to require a certain amount of power, just to spin. So goes for the leds to glow. The best voltage fans can handle 5v at their lowest point, and most normal fans are often 7v low. But taken on a 12v scale, 5v is still @ 40% and 7v is 60%.

If you try to run the fans below their threshold, at 20%, results can be sporadic at best. So in bios or software, whichever you run, the fan curve minimum % must be at least 40% or could be as high as 60%, with a max of 100%.

Which means you'll normally operate at a more medium speed of 7v-9v, and it's associated brightness, but at sleep/idle modes the fans will drop to a minimum state. Currently, with the direct to molex psu, they don't budge, stuck at 100% brightness.