Fan Noise
In past years, gamers would accept everything for a little bit more performance. Nowadays, users are more aware of their graphics card's fan noise and power consumption.
In order to properly test the fan noise a card emits, we use the Bruel & Kjaer 2236 sound-level meter (~$4,000). It has the measurement range and the accuracy we are looking for.
The tested graphics card was installed in a system that was completely cooled passively. That is, passive PSU, passive CPU cooler, and passive cooling on the motherboard and solid state drive. Noise results of other cards on this page are measurements of the respective reference design.
This setup allows us to eliminate secondary noise sources and test only the video card. To be more compliant with standards like DIN 45635 (we are not claiming to be fully DIN 45635 certified), the measurement was conducted at a distance of 100 cm and 160 cm off the floor. Ambient background noise in the room was well below 20 dBA for all measurements. Please note that the dBA scale is not linear but logarithmic. 40 dBA is not twice as loud as 20 dBA, as a 3 dBA increase results in double the sound pressure. The human hearing perception is a bit different, and it is generally accepted that a 10 dBA increase doubles the perceived sound level. 3D load noise levels were tested with a stressful game, not with Furmark.
The card basically emits the same noise levels as NVIDIA's reference board in both idle and load. These noise levels are quite acceptable for a card in this performance class, though I still find them a bit disappointing since I expected better from such a powerful-looking cooler. At 80°C, temperatures are very reasonable, but there isn't a lot of headroom to reduce noise because the GTX 780 Ti will start throttling around 85°C. So it looks as though ASUS did what they could, but the cooler is simply not powerful enough for a quieter experience.
Don't get me wrong, the card isn't all that noisy (look at where AMD R9 290X is on the gaming noise charts for noisy).