The iMac Pro combines the design of the iMac range with hardware you would expect to see in the high-specification Mac Pro, creating an all-in-one desktop ideal for the professional market. Apple has put together Xeon processors with high core counts, powerful AMD Radeon Pro Vega GPUs, and up to 128GB of memory into the 27-inch iMac case, complete with a twin centrifugal fan system to help keep everything cool.
● 27-inch 5K P3 display
● Space Grey chassis, accessories
● 8, 10, 18-core Xeon processors
● Up to 128GB of DDR4 ECC memory
● AMD Radeon Pro Vega GPUs
● 4 Thunderbolt 3 ports
● 10 Gigabit Ethernet networking
● Starting from $4,999
● Available since December 14, 2017
Revealed during WWDC 2017, the iMac Pro is Apple's attempt to bridge the gap between the prosumer market of the iMac with the professional-centric Mac Pro. The result is a high-specification version of the iMac that offers many of the qualities found in the Mac Pro line, but packaged within an iMac body.
iMac Pro External Specifications
The iMac Pro shares the general external appearance of the larger iMac, retaining the same 27-inch 5K-resolution Wide Color (P3) display and physical design. Like the upgraded iMac announced at the same time, the 5K display will include support for 1 billion colors, and 500 nits of brightness.
To denote its status, it uses a Space Grey chassis, which is only available in the Pro version, as well as matching matte wireless keyboard, Magic Mouse 2, and Magic Trackpad 2 accessories.
Though the chassis is largely unchanged, Apple has incorporated a long vent into the bottom part of the rear casing, to aid the improved cooling system. The collection of ports on the rear have also been upgraded, with the usual SD card reader, audio port, and four USB 3.0 ports, while wired networking is handled by a 10Gb Ethernet port, a first for the Mac.
Four Thunderbolt 3 ports are also included on the back, allowing the iMac Pro to connect to external storage devices and other displays, with up to 40Gb/s of bandwidth available to use. Using the four ports, the pro desktop is capable of running two external 5K (5120 by 2880) displays, four 4K UHD (3840 by 2160) screens, or four 4K (4096 by 2304) displays, all at 60Hz.
Apple claims it will be possible to connect two 5K displays and two high-performance RAID at the same time, using the four Thunderbolt 3 ports.
While it can function with the Pro Display XDR as a secondary monitor, it is unable to output a 6K image, without the assistance of a Blackmagic eGPU or Blackmagic eGPU Pro. On its own, it offers at most a 5K-resolution image.
iMac Pro Internal Upgrades
In order to manage the higher temperatures associated with more powerful components, Apple has designed a new cooling system using twin centrifugal fans. The cooling system allows for an 80-percent increase in system thermal capacity compared to earlier iMac models, in turn allowing the iMac Pro to handle more power, up to 500 Watts.
The cooling changes allows for a far more powerful processor to be used, with 8-core, 10-core, and 18-core Xeon processors said to be up for selection when it ships, with Turbo Boost clock speeds of up to 4.5GHz.
Shortly before the release of the 8- and 10-core models, it was revealed there will be an extra 14-core option, which Apple is believed to announce on December 14.
It will include 32GB of 2666MHz DDR4 ECC memory at its lowest configuration, with options to boost it to 64GB or 128GB. Unlike the iMac and its accessible memory, pro owners will not be able to easily upgrade their systems.
A 256GB RAM option is available, but only as a custom configuration from Apple.
The base model will use a 1TB SSD, with options to upgrade it to 2TB or 4TB SSDs.
The pro all-in-one desktop also features two “enhanced” speakers, as well as four microphones, and a 1080p FaceTime HD camera. 802.11ac Wi-Fi and Bluetooth 4.2 connectivity are also included.
At launch, graphics were supplied by the AMD Radeon Pro Vega GPU, with the Vega 56 with 8GB of HBM2 memory at stock. It was possible to configure the iMac Pro to use a Vega 64 GPU with 16GB of HBM2 memory, providing up to 11 teraflops of single-precision compute power, 22 teraflops with half-precision computation.
Apple suggested this massive graphical performance could be used for real-time 3D rendering and high frame rate virtual reality experiences. During WWDC, Apple impressed attending developers with a live demonstration of virtual reality, indicating the Mac is well prepared to assist those working in that field.
In March 2019, Apple added a new Vega 64X GPU option, which added $700 to the cost of the device at the time of ordering.
Alternate graphical options are available in the form of an external GPU enclosure (eGPU), via a Thunderbolt 3 port.
T2 and the Secure Enclave
A new custom chip called the T2 has been introduced as part of the iMac Pro. The follow-up to the T1 included in the MacBook Pro, the T2 handles a number of discrete functions on behalf of the main processor. Aside from security-focused tasks, this can include handling the system management controller, image signal processing for the FaceTime camera, audio control, and SSD control.
Similar to the T1 and the A-series chips used in the iPhone and iPad lines, the T2 includes a secure enclave, which can be used for storing sensitive information, such as passwords. Notably, it includes a hardware encryption engine, which means storage encryption keys can pass from the enclave to the in-chip hardware encryption engine without leaving the chip itself, increasing its security.
The version of macOS High Sierra used for the iMac Pro introduced a "Startup Security Utility" to take advantage of the T2 chip, where users can enable a firmware password to prevent it from booting from a different hard disk or external media.
New "Secure Boot" options start from "Full Security," which ensures only the latest and most secure software can be run, but requires a network connection at the time of software installation to function. Options for "Medium Security" and "None" are also available, with the former requiring verifiable software to boot, but not the latest release.
A deeper dive into the T2 chip in January 2018 by Jason Snell revealed the T2 as mass storage controller, with "complete control" over the flash storage bank array inside the iMac Pro. The T2 encrypts "every bit" of data sent to the flash storage array, as well as decrypting it, which means that if the flash array is pulled from the computer, the data is irretrievable.
The T2's hooks for the new 1080p FaceTime camera work alongside its new image signal processor, which is able to alter all parameters of the camera, similar to image adjustments automatically made by the iPhone in use.
Pricing, Availability, and AppleCare+
Apple started to ship the iMac Pro from December 14, 2017. The base model started from $4,999, rising to $13,199 depending on the configuration at launch, with Apple comparing the package as better value than a PC equivalent, which it estimates to be around $7,000 for similar hardware.
In March 2019, new GPU and RAM options brought the maxed-out price up to $15,699.
Deliveries commenced on December 27, 2017.
Initially, only the 8- and 10-core models of the iMac Pro were available at launch, delaying the release of the 14- and 18-core models into 2018.
At the end of January, it was reported Apple had started to ship "a small number of early orders" of the 18-core models to U.S. customers. At the time, report sources indicated the 14-core model wasn't shipping alongside the higher-core version, and with no timetable offered for when it would.
Notably, Apple has kept the price of AppleCare+ identical to the iMac, despite the difference in cost. The cover, which extends support coverage to three years from purchase and includes two accidental damage claims, costs $169.
The iMac Pro has many available configurations and can be viewed on AppleInsider's Price Guide. There are 8-core, 10-core, 14-core, and 18-core configurations with various memory and storage options as mentioned above.
PC Price Wars
The pricing announcement for the iMac Pro and its comparison to PC hardware prompted immediate comparisons by numerous parties online. In some cases, PC configurations were able to get close or even undercut the price of the iMac Pro, though with notable issues.
These builds included numerous discounts and rebates in many cases, meaning that they meet the price threshold only temporarily, or requires a potential constructor to perform other actions to receive their rebate.
In some cases, the configured PC systems do not have like-for-like components, such as offering fewer Thunderbolt 3 ports than the iMac Pro, or using Nvidia graphics cards instead of Radeon. Suggested systems also used Gigabit Ethernet ports instead of 10Gbps, and in the case of one build by PC Gamer, even lacked the Windows 10 license, which usually costs $120.
Considering the fluctuations in hardware pricing and the generally downward trajectory for part costs, it is entirely plausible that a similar specification PC could be built for the same cost, or cheaper in the future. More importantly, the proposed PC systems illustrate the potential value of the iMac Pro as a complete package.
It is unlikely such PC hardware price drops and theoretical system builds will dissuade early adopters from acquiring the iMac Pro when it ships.
The first sign of the iMac Pro appeared during an April interview at Apple's headquarters in April, between marketing head Phil Schiller, software engineering SVP Craig Federighi, and members of the media. At the time, it was confirmed work was being carried out to prepare higher-specification iMacs, with configurations intended for prosumer and professional users.
According to Apple's research, approximately 30 percent of the entire Mac user base use pro-level apps at least once per week, for media creation and software development. In that same research, within this group, it was found that the iMac outpaced the Mac Pro in terms of desktop sales, indicating to the company that there was more of a professional market for the iMac than previously thought.
During December 2016, Apple CEO Tim Cook teased there were updates to the iMac on the way, countering rumors of the Mac's demise stating “Let me be very clear: we have great desktops in our roadmap. Nobody should worry about that.”
Aside from the iMac Pro, Apple is also working on a new modular Mac Pro, but it is thought that will ship well into 2018.
It is believed the model number for the iMac Pro is the A1862. A regulatory filing associated with the device surfaced in a filing for the Eurasian Economic Commission.
The customary deconstruction of the iMac Pro by OWC revealed a number of elements not expected to be seen by the user. This includes the elaborate cooling systems used by Apple to keep the machine from getting too warm, despite the use of workstation-level hardware compressed into the slim iMac-sized body.
The most notable revelation from the teardown is that it is technically possible to upgrade the RAM in the iMac Pro, but it is highly impractical for the vast majority of users. It uses four quad-channel modules in 8-, 16-, or 32-gigabyte assortments, depending on the memory amount selected at the time of purchasing.
These modules can be removed and replaced, though unlike the user-friendly opening included in the iMac, upgrading the pro model's RAM requires the disassembly of virtually the entire computer, a risky process that has the potential to damage the display.
While OWC admits it has plans to sell RAM upgrade kits for the iMac Pro in the near future, the risk and effort required to perform the upgrade itself indicates that it would be better for most users to simply buy one with sufficient RAM from the start.
For the default $4,999 configuration, it is discovered the 1 terabyte of storage is in fact made up of two compact 512-gigabyte SSDs, joined together in a RAID configuration, with the setup likely to have been through a combination of cost and space requirements within the packed iMac Pro body. As with the RAM, these drives can be removed, though replacement components will be hard to acquire until long after the initial launch period.
iFixit's teardown discovered another Apple-made chip alongside the new T2. Identified as "338S00268," it was suggested by the repair experts to be the rumored A10 Fusion coprocessor, but later recanted, saying the package is too small to contain the A10's innards.
It is unknown what this newly-discovered processor does.
iFixit agreed that the RAM could be upgraded, though not without a "major undertaking," with the iMac Pro using standard 288-pin DDR4 ECC sticks. The CPU is less clear on its upgradability, as it seems to be custom-made for the iMac Pro, though has the potential to be changed in the future. Notably the GPU cannot be upgraded at all, as it is soldered in place.
The service's customary "repairability" score for the iMac Pro is 3 out of 10, but iFixit added the machine "goes back together just fine" following such a teardown. Plans for step-by-step upgrade guides were also mentioned.