I updated my GTX 1080 FTW's vBIOS (the default one) yesterday and so far it seems to be working fine and I'm not noticing much, if any, additional fan noise. However, temperatures do seem to be a bit lower, for example in Skyrim Remastered on Ultra 4K settings they are around 60-65 C now rather than 65-68 C with the original fan profile. The fan does appear to remain off on the desktop though as it is currently 0% with a GPU temperature of 28 C according to MSI Afterburner.
So what are the differences between the two fan profiles? Does anyone know? Is it just a case of the fans spinning when the GPU gets above a lower temperature, e.g. 50 C instead of 65 C?