iMac Pro Tech Breakdown

The iMac Pro was released yesterday and we are just as excited about it as you are.

Developers of all kinds as well as other creative professionals have long waited to get their hands onto a Mac targeted so clearly to solve the needs of these professions. Since we host Macs by the thousands in our data centers, it is no secret that we are just as excited as you are to get our hands onto these new Macs to see how strong Apple’s new commitment to pro-level computing is. We see the iMac Pro as a teaser of the upcoming Mac Pro which will make our hosting platform even more powerful.

Once it was revealed to the Apple community through a few selected outlets like Daring Fireball that Apple is re-investing into their professional Mac lineup on April 4th of 2017 we have been preparing for the day one of these new machines sees the light of day.

Around summertime, we got the first couple of teasers showing just how incredibly powerful the new iMac Pro was going to be and now we know that these iMac Pros are the most powerful Macs Apple has ever released to date.

Just looking at the raw computing power Apple was able to package into this little space makes it a one-of-a-kind computer design (remember, the case around all this workstation-chip-turning-energy-into-smiles power is the same as the 27" iMac which first went on sale 2012). From rumors earlier this year we’ve heard that the Intel Xeon chips in these new iMac Pros are customized a bit by Apple to allow for it to act nicely with the new T2 ARM chips as well as clocked at a slightly lower base frequency probably to aid longevity due to the compact thermal packaging. Regardless of clock speeds, these iMac Pros are going to be a huge improvement and show real commitment by Apple to support its professional customers' needs.

Looking back at the Ivy Bridge Xeon E5s released in 2012 the list of architectural improvements since is pretty impressive.

• CPU die shrink from 22nm to 14nm
• Tri-Gate transistors (less electron leakage which leads to either increased performance or made the chip up 50% more power-efficient when not under load)
• PCIe 3.0
• Highly improved single & multi-core processing as well as improvements to sequential CPU performance which roughly ended up in a 3% performance gain total across all disciplines.
• Instruction set extensions of all kinds
• Video de and encoding advancements (including support for HVEC the video format used by Apple for newly shot videos since iOS 11)
• Turbo Boost Max Technology 3.0
• Speed Shift (CPU base frequency and voltage control on the CPU itself. Much more efficient clock speed adjustment resulting in less energy consumption)
• DDR4 RAM clocked up to 2166 MHz
• Thunderbolt 3.0 with transfer speeds at up to 40 Gbit/s

It is no surprise that comparing Geekbench results leaves us with a clear winner: the 2017 iMac Pro. To a certain degree that was to be expected (again, architecture advancements & instruction set advancements) but even the base model 8 core iMac Pro should beat the most powerful 12 core Mac Pro from 2013 in Geekbench Single and Multi-Score points by a fair margin. When I say “should” I mean that even though it had been reported, we have no actual results of the 8 core / 16 threads Intel Xeon W-2140-B processor clocked at 3,2 GHz because the Geekbench results show that processor running at only 2,4 GHz. Since there are no actual scores I would guess that the Geekbench Single-Core Score will average out at around 5100-5300 points and 29.000-31.500 points for the Multi-Core Score.

Something that immediately sticks out when glancing at the spreadsheet above is that the 10 core model is the best all around configuration and probably the setup that Apple wants most people to buy. It’s the same configuration that Apple gave to a selected group of people in advance and the only model for which we already have reliable, public Geekbench scores.

The 14 & 18 core upgrades probably aren’t worth buying if you don’t run a lot of highly parallelized tasks all day, every day but sure come in handy when trying you really need those extra cores. Groups with those needs that come to mind are video editors, CI job executions (very much bound to your CI workload), and people who process huge amounts of data for example analysis on big databases.

The second thing that only jumped out after comparing the unmodified CPUs on Intel’s ARK was the altered base frequencies of the 8 & 10 core processors. The 8 core W-2140B & the 10 core W-2150B base frequencies have been turned all the way down to 3,20 GHz & 3,00 GHz in the iMac Pro compared to the stock clock speed of 3,70 GHz & 3,30 GHz according to Intel.

The explanation for this could be two-fold:

For one Apple could have turned it down to accommodate for thermal packaging issues but another, and much more likely reason could be that they wanted to offer the iMac Pro in 4 distinct options. It is likely that the 8 & 10 core processors were just too good to draw distinct lines between the models. Seeing the base frequency of the Intel Xeon W-2145 at 3,70 GHz with a Max Turbo Frequency of 4,50 GHz one could imagine that it might be able to score right alongside the unmodified 10 core processor. Which in turn might score alongside the unmodified 14 core version. Since these processors can’t be ordered at Amazon or Newegg we will probably never know.

Nerding out about all these numbers and comparing L1, L2, L3 Caches, CPU base frequency, and Turbo Boost frequency is a lot of fun. Seeing how these machines all compare against each other in Geekbench and looking for explanations why they line up the way they do is good practice for the day the new Mac Pros arrives. We will be ready and able to give good recommendations that accommodate our customers' needs who might not have the time to dig as deep into these topics.

Everyone at MacStadium is very relieved to see Apple invest heavily into their Mac lineup aimed at Professionals and we can’t wait to get our hands onto the upcoming Mac Pros, hopefully in 2018.