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.
In terms of noise levels, none of three cards tested proved overly loud. The X3 OC was the loudest, hitting 41dBa with its fans spinning at 2070rpm, but it was still barely audible over the case fans. The Founders Edition clocked in 1 decibel quieter, with its fans at 1880rpm, while the Suprim X was the quietest card by a decent margin. The Silent BIOS was particularly impressive, spinning the fans at just 1300rpm, proving effectively inaudible to my ear.