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.
While stock thermal performance may be identical to the Founders Edition, noise levels are a little higher. Not by a lot, with the GamingPro OC hitting 39dBa compared to 37dBa for Nvidia's design, but that difference is noticeable to the ear. It's still a very quiet card, mind, just not as quiet as the Founders.