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 the 3DMark Time Spy stress test for 30 minutes.
Interestingly enough, the RTX 3060 Ti also proved marginally quieter. In our testing, the RTX 3070 Founders Edition ran its fans at 1700rpm, while for the 3060 Ti, it kept them slightly slower at 1530rpm. That resulted in noise levels decreasing by 1dba, which the human ear would be unlikely to notice, but it was picked up by our sound meter.