There used to be a time when the gap between Apple products made choosing the right computer obvious and easy. The deliberate compartmentalization of prices and features clearly dictated which laptop or deskop machine was right, with minimal overlap between the categories.
But as Apple expanded its line-up, and as technology became faster and more efficient, overlap became unavoidable. Nowadays, the line between consumer and professional hardware is blurrier than ever. With the arrival of the Mac Pro last year, and the introduction of the iMac with 5K Retina display in October, what once was an obvious decision is now muddied with tradeoffs.
Neither the Mac Pro or the 5K Retina display iMac was designed with your average customer in mind; starting at $2999 and $2499, respectively, the price alone dictates that these computers are beyond the budget for most buyers. At this level, potential customers -- businesses and universities included -- are expecting a high-performance machine, which is exactly the territory of the Mac Pro.
The Mac Pro is specifically aimed at those who need workstation-class performance, and aren't afraid of workstation-class prices. It was designed and built around powerful, user-replaceable parts, with a system architecture that emphasizes performance without bottlenecks, including PCI Express gen 3 for 40GBps bandwidth and for expandability, four USB 3 ports and six Thunderbolt 2 ports using three separate bus controllers.
Besides supporting up to 36 connected Thunderbolt devices -- 36! -- the Mac Pro also supports up to three 4K displays or six Thunderbolt displays. The Mac Pro setup I reviewed packed an 8-core Xeon E5 processor clocked at 3.0GHz, 32GB of 1866MHz DDR3 ECC memory, a 512GB SSD and two AMD FirePro D700 graphics cards. It was the fastest Mac I have ever used and it breezed through a project render I conduct on my review units using software that isn't even optimized to take advantage of the Mac Pro's features. But, as I said, this performance doesn't come cheap. Although the Mac Pro starts at $2999, the review unit, as configured, cost $6,799 -- and you still have to bring your own monitor. (But, did I mention you can bring six of them?)
The iMac with Retina 5K isn't exactly a slouch. The iMac I reviewed featured a quad-core 3.5GHz Intel Core i5 chip, 8GB of 1600MHz DDR3 memory, a 1TB Fusion Drive and an AMD Radeon R9 M290X. It easily handled everything I could throw at it in the six weeks I spent with it, including editing HD video in Final Cut Pro. But let's not exaggerate: if you have software that utilizes every available bit of power of a 12-core Mac Pro, the performance of this iMac isn't going to sway you. Even if you upgrade the processor to an Intel Core i7 (which, if you're going to buy this iMac, I would recommend), the Mac Pro will still beat the iMac if the software you're running supports the Pro's architecture advantage.
And that's the kicker. While the Xeon-based CPUs on the Mac Pro are indeed powerful, the real benefits are from its dual-GPUs, whose normally idle cores can be utilized for processing by the operating system and supported apps. In concert with OpenCL and other supported APIs, applications can lean on the more powerful GPUs for general processing. This is exactly what the Mac Pro is built for.
But there's a really important caveat. Applications need to be written to take advantage of those capabilities; it doesn't happen automatically.
The Mac Pro and the iMac can both run Final Cut Pro and Photoshop, and you'd expect better performance from the pricier Mac Pro. But the iMac's hardware supports OpenCL -- as all shipping Macs now do -- and, the iMac even beats out some of the low-end Mac Pros in specific benchmarks. That easily puts its consumer-grade performance in the "good enough for professional work" class. That makes the iMac good enough for many entry- and mid-tier Mac Pro customers, especially if you consider the iMac's real strength: the stunning 5K Retina display.
That screen is the best display on the market built into an all-in-one unit. It features 14.7 million pixels -- an insane resolution of 5120-by-2880 pixels -- packed onto a 27-in. screen. Colors are vibrant, blacks are deep, and the amount of screen real estate available makes it very difficult to go back to regular monitors.
Simply put, this iMac has the best screen I've ever personally used -- ever -- and that reason alone should make it worthy for graphic designers, video editors, and literally anyone doing any kind of job that requires reading onscreen text for a significant amount of time.
Apple sells a third-party 4K display on its web site, the Sharp 32" PN-K321 4K Ultra HD LED Monitor for $3,595 (though, Amazon sells the same display for $3459). There are other, cheaper 4K monitors out there, but you must be careful that their specs fit your needs; some of these monitors ship with 30Hz refresh rates. That's going to be useless for most people because motion on the screen won't be smooth.
If you're in the market for a 5K display, Dell sells one. It requires two DisplayPort 1.2 connections, currently costs the same as the entry level iMac with 5K Display, and is so bleeding edge, there's no guarantee that performance will be the best, or even acceptable on the currently shipping Macs, including the Mac Pros. The technology is so new that there's a lot of potential for problems.
Setting that issue aside, the iMac 5K with a processor and memory upgrade would still be still cheaper than a Mac Pro and a 4k/5k monitor combo. By a lot.
It used to be that you could decide between two computers by how much room they took up on the desk (or floor) or how loud or quiet they were under a heavy load. Those issues don't really come into play here. Both the Mac Pro and the iMac are stylish and take up minimal room on the desktop. And from my time with both of them, they're both equally quiet under operation.
That means the decision really comes down to absolute performance vs. absolutely-best screen.
There are those that want or need the best performing computers, and the desktop form factor --with its always-on power and components designed without mobile constraints -- is their best choice if money is no object and performance is key. The iMac's screen advantage won't last; eventually, third parties will offer competitive displays that will meet or beat what the iMac offers today. But you'll have to wait for that to happen.
If you're trying to decide between a Mac Pro or the iMac, ask whether your software supports the Pro, and whether the speed gains you'll see with the higher-priced hardware is worth the extra cost. If you don't need that absolute level of performance, the over-all speediness, comparatively lower price and the absolutely gorgeous display, makes the iMac 5K a tough value to ignore.