Corsair Link ~ CP FAN H115i

Odd little problem here. I have a curve defined for an H115i, which of course is setting the H115i fan speeds according to the H115i temps. It all works just fine. But I have a system fan that uses Commander Pro to set a fan to the same speed as the H115i fans. It has a curve defined that never drops the speed below 600rpm ( they are ML fans, so that's fine ) and the monitored signal is the H115i temperature. In other words the system fan should be proportional to the H115i fans. Works great. Mostly. The problem is when I turn the PC on that sometimes the fan cycles from off to on for no apparent reason. If I go in the LINK and edit the fan monitoring - changing it from say H115i to CPU then back again, everything works as it should. Most of the time. Sometimes it needs that process repeating several times.

I replaced the fan, it made no difference. I tried the fan on a different Commander Pro output, it made no difference.

At the same time I have another fan that is running from the CPU temp and that runs just fine. Never seen an issue with that.

The H115i runs OK too.

It seems that the Commander PRO is utterly unreliable when reading the H115i temperatures, until you give it a poke, then it will sometimes work just fine.

Has anyone else encountered this issue?

Also, can anyone tell me if it is fine to use an un-powered splitter to just drive the fan directly from the H115i - that would mean the H115i is driving three ML140 fans. ( I think it's OK, but I better check ).

It seems that the Commander PRO is utterly unreliable when reading the H115i temperatures, until you give it a poke, then it will sometimes work just fine.

The CLCP does not read the H115i temperature, but rather the control software writes the H115i temperatures to CLCP register 0x26 (WriteFanExternalTemp).

Given this I suspect your issue is down to a bug in CL4 meaning the control temperature does not get written as it should, advise you log a call via https://support.corsair.com/ and ask for this to be addressed.

When the CLCP LEDs are controlled by a temperature this works in much the same way and it would provide insight if you also controlled CLCP connected LEDs with the H115i temperature. Do the Fan and LEDs go wonky at the same time?

Running 3 x PWM fans from the H115i using 4-pin power splitters should be fine. Double check the total current is < 2.0 amps and I advise < 1.8 amps.

Thank you!

The LINK always shows the correct temperature. So it must be writing to the Commander Pro that is failing. LINK may be writing a zero or something to the Commander Pro. This may have the effect of switching the fan off? I dunno. The other possibility is that when the value is updated by LINK that for some reason, just that particular temperature causes it to glitch and temporarily switch the fan off.

Overwriting the control curve seems to get it working again. From what you have said I am guessing that the control curve is processed by the Commander Pro. In that case it would tend to indicate that actually the Commander Pro is sometimes glitching when the Hi115i temp is written.

But certainly the H115i does not suffer the same problem which again tends to suggest that it's Commander Pro thats failing not LINK.

I don't know how the LED control works, but it would be interesting to look at that. At the moment there are no LEDS on the CLCP. Where would I get some addressable leds to plug in to the CLCP?

I have done as you suggested and raised a ticket. I am not sure whether I will monitor the situation with the Commander Pro or just connect the fan directly to the H115i and be done with it. The fans are ML140's so the current should be well within the 2A.

Where would I get some addressable leds to plug in to the CLCP?

Yes, you understand correctly. I have known CL4 report stale temperatures, so just because CL4 reports the H115i temperature this does not mean that is what the H115i is reporting. To know for sure you would need to use another program to check and I would obviously use my SIV utility.

A SIV user uses his cooler temperature to control his CLCP connected case fans and when I checked he has no issues so I expect your issue is down to CL 4.8.0.82.

For LEDs you can either get the expensive Corsair ones (see the sticky thread) or if you can solder do as I did and get 3rd party ones, see http://forum.corsair.com/forums/showthread.php?p=907769.

It would be easier to help you if you used http://forum.corsair.com/forums/profile.php?do=extra