Some reviewers say yes, some say no. What's the truth?
Yes, the Yoga 3 Pro has a small fan.
Where is the fan located?
It is located to the rear right of the keyboard, between the Backspace and Delete keys and the watchband hinge.
Does the fan have vents?
Where are the vents located?
The exhaust vent is located on the rear right edge, above the hinge, about 4cm from the right corner. There is a similar, smaller vent located about 10cm from the right corner. It's where the processor is and presumably allows air in.
Do the vents get blocked in tablet mode?
No, they are positioned such that they are not blocked in any of the Yoga modes.
Does the fan make a lot of noise?
It only comes on when the processor is under high load. I've owned a lot of laptops, and this is the quietest fan I've met.