Apple originally announced the iMac Pro back in June, so if you're in the market for a computer like this, you likely already know most of what I'm about to tell you.
The death of extremely high-powered Macs since the "trash can" Mac Pro has raised the stakes and the interest level among pros for this machine. So people are paying attention and probably are already speccing out their dream machine even as you read this.
But for the sake of completeness, here's the deal: the iMac Pro features Intel Xeon W-class processors with 8, 10, 14, or 18 cores — though for most tasks, Apple seems to be directing people to the 10-core model because its higher frequency is often more important than simply adding cores. You can also choose between two Radeon Pro Vega graphics options.
THE SPECS
It comes with four Thunderbolt/USB-C ports, four USB-A ports, 10Gb Ethernet, and SDXC card slot that supports UHS-II speeds, and a headphone jack. It has the same screen as the current 27-inch iMac Retina 5K and it is as beautiful on the Pro as it is on that other machine. The iMac Pro also has the usual complement of RAM and storage options — though "usual" in this case of course means top-flight components and the opportunity to get as much as 128GB of RAM. (The base model has 32GB of RAM and 1TB of storage.) Apple says that the entire system has been optimized throughout so the iMac Pro will perform better than a custom-built workstation using the same components. Apple also argues that building a comparable workstation with comparable components will end up costing you as much or more than the iMac Pro. Much of that integration comes thanks to new, custom silicon that Apple is calling the T2. It's an integrated system that handles a ton of the deep computer controls that are usually handled by disparate parts of the motherboard. It handles audio, the image processing for the upgraded 1080p camera, and other system management functions. It also acts as a more powerful SSD controller, handling the compute load of file encryption directly rather than having it bog down your main processor.
If all those specs make your eyes glaze over, there's a simpler bottom line: where the MacBook Pro is a computer that makes sense for pretty much anybody, the iMac Pro really is meant for "professionals."Defining that word in the context of the iMac Pro is tricky, but in a general sense it's people who are going to need very powerful processors and modern graphics cards to do intensive computing tasks. Think VR development, working natively with 8K video, scientific modeling, machine learning, and the like.
Apple made the aggressive decision to cram all of that power into a form factor that's essentially identical to the current 27-inch iMac. It has the same 5K screen, the same dimensions, and the same stand. The differences on the outside are subtle. The air vent on the back is a little bigger and blows out a little hotter, but it still should remain silent most of the time. It comes in a darker Space Gray color and comes with black accessories — even the power cable and included Lightning cable are black (and no, you can't buy them separately, sorry).
Apple says that people really do love that form factor. But I also have a hard time wrapping my head around the idea that I would want a machine of this caliber that is not user-upgradeable in any way. Theoretically, a service provider could upgrade some of the parts in this machine. Practically, that won't really happen. The only accommodation Apple made is allowing users to remove the stand and replace it with a standard VESA mount themselves.
In Conclusion...
If you're going to buy this machine, my opinion is that you should know precisely what you plan on using it for — with more clarity than other computer purchases require. That's not just because the price is exorbitant compared to consumer-grade computers, either. It's also because if you simply need a radically powerful machine, there's another professional-grade Mac coming next year, the announced but as-yet unseen Mac Pro.