Wait, but Dell Precision 7000 is a laptop? you can't compare with a desktop. I just built a good gaming PC that can be overclocked including a GTX 1080 for just $2300 (monitor excluded).
I'm sure with $4700 more it's possible to get something still better than this new imac pro.. yet with a good cooling system and upgradable at any time.
edit: $2300 INCLUDING 15% taxes