Question BeQuiet 2200rpm PWM not seen on Asus z390-i

Oct 19, 2020
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Hi Geniuses, First time builder having a meltdown over maybe nothing? I have 2 BeQuiet Silent Wings 3 PWM fans for front of the case and the rear. They are connected via an Akasa fan splitter on the single Cha Fan input on the Asus Rog Strix Z-390i. The fans work but they are not seen in the Bios. Would updating the bios help? Anyone got any thought/advice please? Thank you!
 

Paperdoc

Glorious
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A couple of things to check.

First, you might just have a bad contact in the wiring. The fan's speed signal is generated by the fan and sent back to the mobo on Pin #3 of the connector. So if the connection between a fan and the Splitter output is poor on that pin, or at the Splitter to the mobo header, then the signal might not get through. Try simply unplugging and re-connecting a couple of times on each connection in case that will clean off some dirt and re-establish the connection. While you are at this, examine the connectors for possible loose wiring.

Secondly, IF the Splitter involved has more than two output "arms". there is a small issue to look for. Any mobo header can only deal with the speed signal from ONE fan. So all Splitters will only send back the signal on Pin #3 from ONE of its fans, and ignore all others. Most commonly this is done by simply omitting Pin #3 on all except one of the male output arms. Thus there MUST be a fan plugged into the only output that has all 4 pins.

Not having the speed signal detected is only a very small problem. It has NO impact on ability to control speed - the mobo does not need that info to do its job. It does affect the header's second function, though - that is, to monitor the speed signal for fan FAILURE, and warn you if that happens. No speed signal is interpreted as no fan functioning, and can generate the warning. Moreover, without that signal the header cannot check for failure.
 
Oct 19, 2020
2
0
10
0
A couple of things to check.

First, you might just have a bad contact in the wiring. The fan's speed signal is generated by the fan and sent back to the mobo on Pin #3 of the connector. So if the connection between a fan and the Splitter output is poor on that pin, or at the Splitter to the mobo header, then the signal might not get through. Try simply unplugging and re-connecting a couple of times on each connection in case that will clean off some dirt and re-establish the connection. While you are at this, examine the connectors for possible loose wiring.

Secondly, IF the Splitter involved has more than two output "arms". there is a small issue to look for. Any mobo header can only deal with the speed signal from ONE fan. So all Splitters will only send back the signal on Pin #3 from ONE of its fans, and ignore all others. Most commonly this is done by simply omitting Pin #3 on all except one of the male output arms. Thus there MUST be a fan plugged into the only output that has all 4 pins.

Not having the speed signal detected is only a very small problem. It has NO impact on ability to control speed - the mobo does not need that info to do its job. It does affect the header's second function, though - that is, to monitor the speed signal for fan FAILURE, and warn you if that happens. No speed signal is interpreted as no fan functioning, and can generate the warning. Moreover, without that signal the header cannot check for failure.
Thank you very much for getting back to me and the information. Weirdly/luckily the Bios nows sees the fans again. Thank you for your time
 

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