Noise levels and temperatures
All custom GTX 1080 Tis feature a so-called 0dB mode, which means that they won't produce any sound at all when idling. Only the fan of the Founders Edition keeps spinning when idling. As long as you're not gaming or otherwise putting a load on the cards, you shouldn't notice anything when using the other models.
Under load the card from Gigabyte is clearly the quietest. This is quite a turnaround for the manufacturer, as the GTX 1080 from them was one of the loudest in our round-up. On the next page we find out how they managed to turn things around. MSI and ASUS have also delivered fairly quiet cards. The Inno3D card is pretty audible and the EVGA card is definitely noticeable as well. Since only a single fan is driven based on the GPU temperature, it sometimes has to work really hard and you definitely notice that.
All cards remain significantly cooler than the Nvidia Founders Edition. The Inno3D gets the hottest, however it's still well within safe margins.