I've only been able to assess my nvidia-branded GTX 1070 when plugged up to my TV. I've spent about 3 hours now in MacOS doing basic-every-day consumer tasks (Mail, iMessage, Youtube, Chrome browsing, Bootchamp, etc). I even ran Heaven 4.0 (and it stomped the RX 580 in MacOS which was somewhat surprising). Have yet to see a single glitch of any sort. I tested putting the product to sleep and waking it up (very important to me since I have 3 Westmere machines in the house). All is perfect so far. If anyone knows how to make bugs appear, please tell me. Sometime this week I should be able to put the Mac Pro back in the office and take a closer look on my 27" Cinema Display.