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 Fire Strike Ultra stress test for 30 minutes. An idle reading comes after leaving the system on the Windows desktop for 30 minutes.
Now, as for noise levels, here we do see the biggest downside to this card, as the SC Ultra produced about 48dB of noise when under load. This saw the fans ramp up to 2330rpm, or 67%, producing a fair amount of noise – it's not as bad as Vega 64, sure, but this is still much louder than the other 1660 SUPER cards.
Considering the GPU only peaked at 67C, I would suggest the fans have to spin this fast to provide enough cooling for the VRM – remember, the MOSFETs do not contact the heatsink at all, so their cooling is provided solely from airflow. This is likely why the fans have to ramp up as fast (and as loud) as they do.