The original post: /r/homelab by /u/AceKillar007 on 2024-12-28 09:06:48.
I recently bought an HP 2920 J9729A network switch, and the fans are ridiculously loud. So, I decided to replace them with three Noctua NF-A4x20 fans for the chassis. When I went to install them, I noticed that all the wire colors are the same (Yellow, Green, Black, Blue), but the switch has a connector for all three fans, while the Noctuas each have individual connectors.
To make it work, I used the extension cable that came with the fans, cut off the end, and spliced the wires together. After booting the switch, I got a fan fault error. All the fans dropped in RPM, and about 10 seconds later, they spiked back to max speed.
I only installed one fan to test it, and while it worked, the fan fault error didn’t go away. This is the first time I’ve tried any hardware modifications like this, but I found a few Reddit posts suggesting that I remove the tachometer pin from the connector and create a jumper from ground to the tachometer wire.
At this point, if I can’t figure it out, I’ll probably just use black tape, but the nerd in me really wants to find a proper solution. I feel like i have the wires wrong even though there the same color. Any help would be greatly appreciated!
