EagleOD1 :
Which motherboard should I choose? And will they be compatible with a be quiet! Dark Rock Pro 3 and the NZXT Noctis 450 case and will they look good?
Go to Gigabyte website under the Z170 chip set/ platform. You can COMPARE like 4 mother boards.
The UD5 is not much of a Gaming MB but can be used and it also cost less than Gaming 7 motherboard.
Gaming 7 will allow SLI with 3 video cards, much better Audio, has 2- m.2 SSD, and more but it will cost more than the UD5. Also browse You Tube videos on the products, other builds, and go to www.UserBenchmark.com
Be money smart and stick to your budget plan. There are always Pros and Cons with all products and not everyone can have the best of the best all of the time. MSI has some good motherboards too in the $180 to $250 price range.
Regardless of motherboard or chip set, the best valued (price and performance) video card is the NVidia GTX 970.
There are always sacrifices to be made along the line. So take your time and be happy for what you are able to get and build. In 3 to 5 years you'll be ready to move on up to something you saved and prepared for.
Best of luck and be Happy.