What are the best GTX 1080 cards?

The GeForce GTX 1080 chip is a high-end GPU made by NVIDIA. There are a lot of different GTX 1080 cards available, manufactured by different brands. These graphics cards all use the GTX 1080 and offer similar performance, but some there are some slight differences in the cooling solution or clock speed of the GPU. This question handles the specific pros and cons of branded third-party GTX 1080 graphics cards. A general overview of the GTX 1080 chip can be found here.