We take our noise measurements with the sound meter positioned 1 foot from the graphics card. I measured the noise floor to be 32 dBA, thus anything above this level can be attributed to the graphics cards. The power supply is passive for the entire power output range we tested all graphics cards in, while all CPU and system fans were disabled. A reading under load comes from running Cyberpunk 2077 for 30 minutes.
As for noise levels, one consequence of the 3090 Ti being such a high power GPU is that all of the cards we tested were audible under load. Some were quieter than other, with MSI's Silent BIOS delivering the lowest noise levels, but at 38dBa it was still audible to my ear. It's still not loud of course, but you may just have to adjust your expectations – to cool over 450W of power is going to require higher fan speeds than if this were just a 350W GPU, for instance.