I was thinking of passing my 2014 Mac Mini base model (1.4 GHz/4GB RAM/Intel HD 5000) to one of my kids and replacing it with the 2014 Mac Mini mid-level model (2.6 GHz/8GB RAM/Intel Iris Graphics). Rendering graphics a little faster is important to me for some light CAD ad 3D work. But I don't know how much better that Iris Graphics chip is. Also, I'm open to a 2017 MacBook Air in clamshell mode connected to my display. The base model (1.8 GHz/8GB RAM/Intel HD 6000) would be fine from a storage standpoint since all my media is offline on a USB HDD. Basically, which graphics chip is better? The Iris in the 2014 Mac Mini or the 6000 in the 2017 MBA? Thanks!