Why would my GPU suddenly stop throttling back speed when idle?

[Vertigo]

So my GPU (4090FE) has literally just stopped throttling down the clock speeds when idle in Windows.

This has never been an issue before but I've just noticed that the GPU fans are spinning when usually they only do when gaming.
GPU-Z is showing a GPU Clock of 2520Mhz and both fans at 30% despite there being no load on the card at all.

What would have caused it to suddenly stop throttling down the clocks like this?

 

[Vertigo]

Update...

Ok so I tried a complete power-off and back on to no avail.
Then I tried reinstalling the latest drivers, ticking the clean install option.

Now the fans have actually powered down correctly in Windows but the GPU Clock is still showing as 2520 Mhz.
Can't remember if this is normal or not tbh. I thought the clock was supposed to throttle back when not under load but honestly can't remember if it ever did this.

 

[Ascendancy]

It should clock down to like 300mhz when it's idle. Are you sure you haven't accidentally enabled max perfomance mode in the Nvidia control panel or something?

 

[Vertigo]

Well that didn't last long, the fans are back up to 30% again, despite no load.

Performance mode is set to Normal in the control panel.

 

[Ascendancy]

If you boot into safe mode does it still do it?

Got MSI Afterburner installed or something similar that could be conflicting something somewhere?

 

[Vertigo]

If you boot into safe mode does it still do it?

Got MSI Afterburner installed or something similar that could be conflicting something somewhere?

Yep was still doing it in Safe Mode but then I suspect it needs the drivers loaded to throttle it back at all.

I have two completely separate OSes in dual-boot on this machine so I booted into the other one and that was fine, clocking down to 210Mhz at idle.
Interestingly the other (working) OS was on driver version 560.94 whereas the troublesome OS was on the latest 566.36 drivers.

So I've just done a DDU to clean the drivers completely and then reinstalled 560.94 on the problematic OS and so far, it's now working, throttling back to 210Mhz at idle.

Of course it's not clear whether this is just an issue with the latest drivers or some other odd setting that may have been cleared by DDU. Will leave it like this for a day or so before I try re-upgrading the drivers again to see if the problem returns.

 

[Ascendancy]

Oh good. DDU was going to be my next suggestion.

I'm on 566.36 and mine downclocks fine, so I'd point the finger at DDU managing to remove whatever funky stuff was going on.