Hello! I've searched up and down these forums for a solution to this but no dice. I've seen a few people with similar issues but none that specifically have this going on. 

I popped in a brand-new 3080ti FTW3 yesterday and installed PX1, did a firmware update, the usual. Everything was going smoothly, then I went outside for maybe 20 minutes and came back to find my GPU sounding like a jet. Fans #1 and #2 report 0 RPM to PX1, but fan #3 seems to be functioning as intended, as I can read and control its speed just fine. Looking inside the case it's clear that two of the fans are stuck at 100% and one is working as intended. So far nothing I've tried can get the fans working right.
 
I've tried disabling fast boot and disabling CSM (though that just made it so I couldn't get past BIOS and boot into Windows I updated my drive to GPT and am now running UEFI BIOS, still same issue though), force-updated the firmware, unplugged the fan headers on the PCB and re-plugged, cleared CMOS, switched to the OC bios, did a clean boot, DDU'd in safe mode, several other things I'm forgetting. I haven't tried flashing the VBIOS yet didn't work.

Thanks for your time!

Sajin
Sounds like you'll need to rma.

Figures. It was my plan originally to swap out the fan with a hybrid AIO anyhow, so I think I'll save the trouble and wait for those to get back in stock. Everything else with the card works perfectly so shrug. Any idea on the availability of hybrid coolers? I'd like to escape jet plane hell sooner rather than later haha 

besides the immediate firmware that updates immediately there was also another Vbios that it needs that isn't as obvious...
So that might fix your issues.
 
Open PX1 , see the icons at the very top - vga, led, hwm, power, rebar - >  click on the REBAR icon
3rd selection down that page should read as - graphics VBIOS & it probably says to the right of the numbers that an update is needed.
click that & a DOSbox opens up where you usually have to OK it with a "Y" for yes a couple times .
then reboot system after completed =
cross fingers that you are now all good .

Does the same happen also if you boot with a Linux distribution? I am thinking about starting with a random Ubuntu image and see if they spin also in another OS.