node pro Odd Lighting Behavior After Switching Fans Around

[That_One_Person]

I had just finished my new build that has six fans (3 SP120 rgb pros, and 3 LL120 Rgbs) I had set it up and got it working just fine with a Node pro and Rgb hub.

But I had decided to switch the fans into different spots, moving their cable to different ports as well. Now for whatever reason, there are 2 different fans synced up to 2 other fans with the lighting. All of them light up just fine, but when I go into lighting setup the two that seemed to have synced with other fans don't light up.

I can provide more info if needed.

[DevBiker]

Well, you have mixed fans on a single channel. It'll work but it'll cause configuration issues.

How do you have iCUE configured and which fans are connected to which ports on the fan hub?

[That_One_Person]

I have the SP fans on the first 3 ports with the LL fans on the last 3.

It had worked just fine before I had changed them around. Which was originally the LL fans on the first 3 and the SP on the last 3.

[DevBiker]

Right. With LL on the first 3 and SP on the last 3, you'll configure it as 5 LL fans. The first 3 will be perfect ... LL Fan 4 will control SP Fans 4 and 5, then 1/2 of LL Fan 5 will control SP Fan 6.

The fans run in series - one after the other - and the data is passed from one LED to the next and then one fan to the next. The data signal starts, on fan 1, with data for ALL of the LEDs. The first LED takes its data off the chain and passes the rest of the data to the next LED, which does the same. At the end, the data then goes to the next fan but with 16 fewer LEDs (taken from the first LL fan).

Now ... when you mix the order around, suddenly everything is off. The SP fans remove 24 LEDs total from the data chain ... so 1 1/2 LL Fans. The first LL fan, now on port 4, gets the last half of LL Fan 2 in iCUE and the first half of LL Fan 3 in iCUE. So all of the LL fans are off by 1/2 but the SP fans look the same.

By the end of this, hopefully, you'll come to the conclusion that the fix for your problem is to put them back the way that they were OR to separate the different fan types onto different channels. Either option will work. But when you mix fans on a single channel, you should keep the fans with the most LEDs on the first ports ...