Buying the Retina iMac, Instead of a Mac Pro

Before the release of the Retina 5k iMac today it had been almost exactly 4 years since I bought a new Mac. But every time I do there is a lot of analysis that goes into it. With the Retina iMac it was no different, but in this case the analysis started quite a while ago. The path to this purchase began over a year ago with the release of the new Mac Pro. But before going into why I bought the Retina iMac, let me explain why I chose not to buy an iMac when making an almost identical decision 4 years ago.

I've always used a Desktop Mac as my personal Machine, and the choice has always been between iMac and the Pro lineup of towers. I switched to towers in 2004 after three different generations of iMacs and and I was very happy with it. The performance was well worth it for the price, with dual G5 processors for $2999. That machine proved to be very capable and served me well throughout my college career.

That lead to 2010 and the release of two amazing new Mac products: The 2010 Mac Pro, which would become the professional Mac user's workhorse for nearly 4 years until the space age Black Cylinder Mac Pro was released last year. And the 2010 iMac, featuring a gorgeous 27" display, Core i7 processor, desktop grade Radeon 5750 graphics, and internal SSD storage. Both machines provided out-of-this-world performance and at very similar price points. Here's a chart that I made 4 years ago for the stats on each machine and the effective price.

2010 iMac vs. Mac Pro

2010 iMac vs. Mac Pro

The Mac Pro turned out to be about $500 more expensive than the iMac, but the iMac had an integrated Cinema Display. The display in the iMac has not always been the best in the world, but with the 27" Cinema Display it was pretty close. This was a significant factor in the iMac's favor. In terms of CPU performance the two were about even, honestly with the iMac beating out the lower tier Mac Pros in every-day tests. The best CPU I could afford at the time was the Xeon 3.2GHz Nehalem, rather than the impressive and consideraly more expensive 6-core Westmere, but the Nehalem proved to be beefy enough. It also turned out that the Radeon 5870 in the Mac Pro did outperform the iMac's internal graphics by a significant margin in most benchmarks, but this alone didn't tip the scales.

Certainly a major factor in anyone's computer purchasing decision is what they intend to use it for. As a professional photographer a critical component for my personal computing needs is fast, reliable, and MASSIVE connected storage. In those days, the options for cost effective reliable external storage were not great. I've written about external storage before, and in general the price increase over internal storage has usually been huge. In 2010, a properly equipped Drobo would have cost north of $1200, and been connected over either Firewire or USB - not nearly fast enough compared to SATA. That and reliability concerns with Drobo and other manufacturers at the time were enough to steer me away from external storage. In effect, I ended up choosing the 2010 Mac Pro almost entirely because of it's internal storage capability and how that effected both storage reliability and performance as well as a significantly lower total system price. That ended up being an extremely wise choice. I now have 4x4TB internal drives in my Mac Pro, for a total of 8TB of redundant RAID Mirrored storage. I currently rely heavily on the Mac Pro's internal storage.

If all of the above considerations were still true today I probably would not have bought a new iMac today. But two things have changed dramatically in the last year that really tip the balance for me, and I think for many other professional and pro-sumer desktop Mac users.


The first is the way in which expandability works on high end desktop Macs. In previous models  the most important form of expandability was internal. Certainly there are cosmetic benefits to internal expandability in the form of simplicity and having a clean desktop working environment. But the biggest benefit was performance. Having access to an internal SATA bus for storage was critical. Having access to PCI slots to install additional cards was a key requirement for many users. Even having access to RAM slots or the GPU was important to many people. You could even upgrade the CPU on the Mac Pro if you really wanted to.

But all of that has changed over the years. Apple has begun bundling more and more components permanently into products. First was the CPU and graphics in the iMac and Laptop lines, then came RAM and storage being soldered onto the motherboard. The iMac and Laptops were never easily expanded but pro users always had the option of purchasing an expandable Mac tower if they needed that feature, until the new Mac Pro debuted last year. The new Mac Pro leveled the playing field for expandability. Now all of Apple's products had the exact same expandability option: Thunderbolt.

My friend Thomas Duesing really nailed this 4 years ago. In discussing whether or not the iMac or the Mac Pro were the right call back then, he pointed out that all of this logic would change if Lightpeak (now Thunderbolt) were available. Well here we are in 2014, and Thunderbolt 2 is the missing link in expandability across the Mac lineup, not just for storage but for other accessories as well. Thunderbolt allows you to add super fast SSD storage, bulk HDD storage with better than SATA performance that is no longer limited by USB or Firewire, and best of all: PCI slots. With accessories available from OWC, you can add PCI slots to an iMac for the first time in that product's history. The expandability fight between the iMac and the Pro desktop is now dead even, and all it took was the Mac Pro dropping internal expansion from it's lineup. Accessory makers took notice of that and created a whole new lineup of products to fill that market. The results of that are huge for the professional market, and are now making it possible for someone with professional storage needs to consider any of Apple's Mac products as a viable option.


The second and most obvious change in the calculus between the Mac Pro and the iMac is, of course, the display. In 2010, the bundling of a 27" Cinema Display was essentially a nice to have. Afterall, an equivalent monitor was an expensive but available $999 accessory to any other Mac computer. Now, though, the iMac has a tremendous advantage. I haven't seen the new 5k Retina Display in person yet, but I have no doubt it will be absolutely stunning. When I was at CES this year I went around to every display manufacturer to see their 4k computer monitors, and all of them were simply gorgeous. I would have used any of them as a desktop monitor, and for most of December/January I desperately wanted to. That was when my purchasing decision began: should I continue using my 2010 Mac Pro, or go all in on the new Mac Pro with an external 4k monitor?

But by early 2014 it was clear that there were actually a lot of problems with 4k monitors on the Mac. For starters, most Macs weren't capable of powering them - only the new Mac Pro and the latest retina MacBook Pro were capable of running them above 30hz, and even then only with the right model displays. The 4k monitor sold in the Apple Store by Sharp was capable, but this monitor sells for $3595, over $1000 more than the basline retina iMac does. Moreover, driver support for these monitors in OS X was poor. OS X Mavericks didn't include support for scaling the resolution of these screens the same way that it did for the Retina Display in the MacBook Pro. As a result, icons and text were rendered unusably small for everyday use, even if photos and video were beautifully sharp. At best, these monitors were only useful as extra monitors for detail-checking photos and 4k video - not as monitors for normal every-day productivity.

All of that has dramatically changed with the 5k Retina Display on the iMac. We got our first hint that this display would hit the market about a month ago which is when rumors started running rampant about the retina iMac. This display would literally pixel double the existing display in the Apple Cinema Display and 27" iMac, making it the perfect solution for a retina Mac desktop monitor.

For the photographic professional and anyone interested in fine pixel level detail this display is the best there is. To me, it's an absolutely must have. Now that expandability has been equalized, the existence of this monitor tips the balance enormously in favor of the iMac. Honestly, without the existence of an economically priced external monitor of the same quality, it's hard to justify the purchase of a Mac Pro at all, except for extreme cases where raw workstation grahpics and multicore CPU performance are required.

When I re-recreate my 2010 chart for the new Retina iMac and latest Mac Pro, and also factor in the purchase of an external display, the results are stunning and obvious. 

2014 iMac vs. Mac Pro

2014 iMac vs. Mac Pro

When you include the purchase of a new monitor the Mac Pro costs more than double what a retina iMac costs with similar specs and likely similar performance in real-world tasks. In the chart I chose to max out the graphics processors on both models, since the graphics on both are not upgradeable, and having the best graphics possible makes the most sense from a product longevity standpoint. Of course, and equivalent display to the 5k Retina Display on the new iMac does not exist, but I went with $2499 as the estimated price, because of the article by Anandtech claiming that as the eventual price point

Of course, this comparison is further complicated by the fact that the current Mac Pro (and all current Apple computers) are incapable of powering that Dell 5k monitor at all, let alone over a single Thunderbolt port. This is also why the retina iMac does not appear to work at full resolution in Target Display Mode - because no Mac can actually run it as an external monitor. This consideration makes the Retina iMac the only choice for a desktop Mac with best-in-class display performance.

So those are all of my reasons for going with the Retina iMac now. But there are still some possible concerns that I have about the machine.


The biggest one has got to be graphics. Driving that many pixels is going to be taxing for any GPU hardware, and will likely be quite a task for the AMD mobile GPUs included with the new iMac. I know from experience that this can be the case, because of what happened to mine and several other 1st generation Retina MacBook Pros. About 6 months ago, the GPU on my 1st generation Retina MacBook Pro died suddenly. It was replaced under Apple Care, but I expect that it just burned itself out working so hard to power that display. It's possible that the same thing could happen on the Retina iMac. Because of this, I would recommend to anyone considering the purchase of one that they upgrade the GPU to the 295X, just to be safe, and that they also purchase Apple Care (as I did) to offset the financial risk if an issue does arise.

Of course, there is also the possibility that the machine will simply be underpowered, certainly compared to next year's model or even to an eventual second generation Black Cylinder Mac Pro with the hopefully inevitable external version of the 5k display. So why not wait until next year and see how the rest of the desktop landscape shakes out?

For starters, I think I have waited long enough for this level of quality machine. While my Mac Pro may only be 4 years old, the three displays connected to it are each nearly 10 years old. I've still got the original 20" Aluminum Cinema Display that I purchased in 2005, and two additional ones of the same model that I purchased used more recently to pair up three of the same monitor on my Mac Pro. I love the three monitor setup, but the quality of these displays is clearly lacking compared to even the normal Apple Cinema Display. I held off purchasing one of those in order to wait for something like this, and I want to take advantage of it immediately. I don't want to wait to get 5k Retina.

But personal feelings aside, I've learned that when Apple releases an obviously breakthrough product like this that the time to jump onboard with it is immediately. There's no way to tell when an external version of this display will be available. Given the support in the rest of Apple's hardware landscape, I don't think I'd expect it to happen next year. We were hoping for a retina iMac last year, and it took an additional year from those rumors. From the early reports I am reading, Apple is having to bend standard specifications like Displayport just to get the iMac to work at all. I don't think they are ready to standardize this into a standalone product just yet, or I think they would have already done so with this one. And even when the external version does come out, it will still likely be priced higher than $999 initially, and will still require the purchase of a separate and very expensive Mac Pro. 

The place where I would still feel conflicted is for users who require their personal machine to be a laptop. Some people prefer to use the same machine at work and at home, which I can understand. But I don't have any issues swapping between a laptop at work and a desktop at home, as I have done for many years. Some people work for themselves and can't afford to purchase two machines, which also makes complete sense. In that scenario, having a laptop is usually of utmost importance for portability reasons. In that scenario I think the price of the iMac at least makes this conversation a much easier one. $2499 for even a baseline Retina iMac may still leave a bit left over for at least the purchase of a baseline MacBook Air, which may satisfy the portability needs of some users considering a pro level Mac desktop. For some users, an iPad may also be a suitable portable computer.


But even disgarding the display as a key advantage for the iMac, the level expandability playing field would still favor the iMac because the only real advantage of the Mac Pro would be extreme multi-core CPU and GPU processing performance. For the photographer, and likely for many professional and pro-sumer Mac users, that advantage isn't enough to tip the balance.

Regarding expandability, I want to share two more key details about how I plan to actually use my Retina iMac. There are two products from OWC that made all the difference to me in considering the purchase of the new Retina iMac.

The first one is the OWC Mercury Helios 2 PCIe Thunderbolt Expansion Chassis that supports Thunderbolt 2 and allows the addition of two PCIe card slots to any Thunderbolt Mac for a somewhat expensive but still worth it price of $498. Some users may require this product for adding eSATA slots or something else, but I personally plan to use it with my two OWC Mercury Accelsior PCIe SSD drives that I bought for my existing Mac Pro last year. In a stripe configuration, these drives deliver over 1000MB/s read and write performance, which outperforms a standard SSD by a considerable amount, and should even be faster than the built in PCIe storage in the Mac Pro and Retina iMac.

The second one is the OWC ThunderBay 4, a Thunderbolt 2 capable RAID-ready 4 drive bay for fast and reliable external storage. Basically, this $459 device lets me swap my four 4TB drives straight into this enclosure from my Mac Pro and continue using them without any performance hit that would typically be associated with USB, Firewire, or iSCSI. 


The time feels right to move back to the iMac. 10 years ago the performance gap between an iMac and the PowerMac G5 was absolutely massive. But by 4 years ago the gap was much smaller, and as of last year the situation had actually reversed itself. When the new Mac Pro was released and benchmarks started to appear I was shocked to find that the iMac actually beat the Mac Pro on many benchmarks, including most gaming tests and several real world app tests. Clearly now that the differences of expandability are moot the iMac has asserted itself as a viable computer for professional Mac users.

One of the things I wrote about my purchasing decision to some of my friends 4 years ago was the topic of longevity. Spending over $3000 for a computer is a big deal these days, and you want that purchase to last you a long time. I got over 4 years of life from each of my Mac towers. I believe that I can get 4 years of life out of this iMac too. One reason for that is expandability through Thunderbolt. I know now that I can add as much storage as I would ever need through that, and the inclusion of Thunderbolt 2 means there should be plenty of available throughput to expand into over the years. I expect the availability of great Thunderbolt accessories to grow dramatically as well, even more than has happened over just the last year. But I also know that I tended not to leverage my Mac tower's expandability to it's fullest. I never upgraded my GPUs, CPUs, or other components beyond RAM and storage. I'll max out the iMac's RAM through OWC, and add Thunderbolt external storage, and I fully expect that to last me for years to come.

But the real deal is the 5k Retina Display. What I told my friends at work today is that I could easily see myself spending weeks just looking through old photos in my library on the new display, just because of how different they're going to look now on a better monitor. That's when I started to consider just how silly it was to have a $1999 Canon 6D that shoots super detailed 5472x3648 images but with no good way to enjoy them on a 1680x1050 10 year old monitor. The new 5k display is the sort of monitor that would make switching from Aperture to Lightroom fun, because of how great it's going to be looking through all of my old high resolution photos and seeing them in a new way. And of course, re-playing a few great games and writing a few new iOS apps should be fun too.

All in all, I see the Retina iMac as being the computer that I want to use for the next 4+ years. That's what made it an obvious buying decision for me, even on day one, and even though it means leaving the Mac tower after 10 years and switching back to the iMac lineup. Now just feels like the right time to do it.