It should be there, at least the description for nvidia-setting’s gpufantarget implies:
I don’t see how that would imply anything about detecting more than 3 fans. Both fans 1 and 2 are reported as targeting “GPU, Memory, and Power Supply.” So obviously the third one would be the same, or Nvidia-settings isn’t actually reading what they’re actually supposed to be targeting, either way it doesn’t imply anything about more than two fans.
- bug in nvidia-settings or driver
I think this is the most obvious solution. Nvidia has never made a card themselves with more than two fans to my knowledge, and there is so much old legacy crap in the Linux (and probably Windows but idk) driver that it’s REALLY easy to believe that they just never even added an interface for a third driver. And since they don’t use hwmon, we can’t look and see if Linux itself is detecting it (which it is though, because sometimes randomly it will work, but VERY rarely, and I can never force it).
- third fan not defind in reference design so vendors use a different interface
I mean, if that were the case, fans 1 and 2 wouldn’t be individually controllable either. But they are. And I find it pretty unlikely that they would what, use the defined interface for fans 1 and 2 but use some crazy one for fan 3? And even if that were the case, it wouldn’t prevent Nvidia from adding support to the driver, AMD GPUs are able to detect all three fans no matter who makes it, and AMD hasn’t added anything vendor-specific to their drivers.
- Do you use some vendor-specific application to control the fans in Windows?
Well what’s a non-vendor-specific utility I could check to see if all three fans are detected? Obviously I use Precision X1 because it’s an EVGA card. But if there’s something else, I’ll check and see what happens.
But I mean, regardless the bottom line is that Nvidia needs to add support for a third fan into their drivers. Running a 375 Watt $1700 USD GPU with 2 fans on a heatsink designed to run 3 is NOT a good idea, and not to mention that third fan is honesttly one of the most effective since it’s where the passthrough part of the card is, so it’s just blowing straight through heatsink with no PCB blocking it. So it cools down the whole card. I need this fan.
I’ve even tried booting into my VFIO VM (single-GPU passthrough) and maxing out the fans and then shutting it down in hopes that the fans would stay maxed out when I log into Linux, but essentially the card resets when that happens so it’s as if I rebooted, and nothing gets saved.