Anthony’s Mac Labs Blog

The Mac Desktop Dilemma

Posted 2018 November 04

Since I run labs at my place of work, I only deal with desktop Macs. As a complication, we use matte (non-glossy) displays in our larger lab, since we edit and print digital photographs (and other digitally-produced art) in that space. So this week’s announcement of a new Mac mini was of great interest to me. As much as I’d like to have a lab full of Mac Pro computers to attach to those matte displays, public institutions don’t have that kind of money, so the Mac mini has filled an important role for us—and with this week’s announcement, I expect it to do so for some time to come.

Having said this, we have one smaller lab where we tried iMacs. Those worked out fairly well for that space, so now that they are due for replacement, I spent the time immediately after the announcement trying to determine whether the new Mac mini could compete with the 2017 27-inch iMac on price and performance, keeping in mind that my users are in the Arts and require features that many users do not. Here’s what I found.


The existing Mac mini (2014) computers we have are looking long in the tooth. If it weren’t for the Fusion drives in all of them, they would be too slow for our needs at this point. The fact that the new Mac mini is back to offering 4 processor cores (or even 6 cores if you spend the extra money) instead of 2 already makes these a boon for some of the software we use. There is one detail to consider, though. The new entry-level Mac mini uses an i3 processor, which lacks one ability found in the i5 and i7 processor series: those processors can increase their clock speed when not all the cores are needed (“Turbo Boost”). For organizations that were purchasing the previous entry level Mac mini (especially the 1.4 GHz model), they should see a strong performance increase, even considering the lack of “Turbo Boost.” If you were purchasing something higher up the line (perhaps even a custom build like we did), it appears that the Mac mini has finally brought itself even with the iMac in CPU performance at a comparable price point.

There is one caveat to that statement, though. The 27-inch iMac uses a dedicated graphics chip (GPU) with a minimum of 4 GB of dedicated memory. The Mac mini uses the integrated graphics processor that is a part of the i3/i5/i7 CPU, which also has to steal from your main RAM to do its work. (I’m guessing it will need about 2 GB of RAM based on the fact that the previous Mac mini used 1.5 GB.) Since artists are heavy users of my labs, we definitely do a lot of “graphics” work, but understand that you don’t have to be doing “graphics” to benefit from a GPU. Many common apps now offload tasks onto the graphics processor. On the iOS side, this is a much bigger deal, where we have seen Apple put a high emphasis on evolving its graphics processors to ensure a silky-smooth user interface. With Apple’s universal framework (code-named Marzipan) opening the door for iOS apps to make the jump to macOS, I could see graphics processors becoming more important on the Mac side.[1] So the new Mac mini seems to be up-to-speed on the CPU side, but the lack of a dedicated GPU appears to keep the iMac ahead for now.


For some of you, the iMac display may be very nice but it is overkill. Maybe you don’t need the Retina/HiDPI display and would be happy with a 2560 x 1440 pixel display of the same size (similar to what the 27-inch iMac used in the 2009–2013 models). Or maybe you need that matte display and the only way to get that with an iMac is to apply a film to the glass or purchase an external display. For those people, the new Mac mini could be an excellent choice. At home, I have one of those prized 2012 4-core Mac mini models, which I upgraded from a 2-drive server configuration to a Fusion drive. It’s still meeting my needs right now, but I suspect when I upgrade it to Mojave, I might not be as pleased (more on that later). The Mac mini remains a good choice for my Mac at home, since my eyes prefer a matte display.

Having said this, maybe that isn’t you. Maybe you have a 5-year-old iMac you want to replace and are wondering whether this year’s Mac mini is a better deal than last year’s iMac. To me, the display included in the current iMac is in line with the kind of manufacturing decisions Apple has been making for the past two decades. I summarize this as, “you get what you pay for.” The 5K display that comes with the iMac is simply unmatched in the 27-inch category. The fact that it supports the DCI-P3 colour space makes it a great choice for video editing—even 4K—and the overlap between the P3 and Adobe RGB colour spaces make it also very functional for doing photographic work (again, assuming you don’t insist on matte displays). Does the Retina display make the iMac cost more than if Apple had cheaped out with a 2560 x 1440 pixel display? Yes, but you get what you pay for. If you try to put together a Mac mini with an external 5K display, the closest you get costs hundreds of dollars more and will not have a GPU. So making an Apple(s) to Apple(s) comparison, the iMac is the better value if the display suits your needs.

If you were limited by the previous Mac mini’s inability to driver higher resolution displays (and had low refresh rates for the sizes they could drive), that is ceiling has been lifted in the new model in a major way. You can even run a triple display setup with modern resolutions—this is the benefit of those 4 Thunderbolt 3 ports on the back. The current iMac can only run 2 displays, but I would expect this to change when the next iMac is released, likely in 2019—I think you will see the same 4 Thunderbolt 3 ports and 2 USB-A ports for USB 3.0 that are on the new Mac mini. Regardless, if you need to run multiple high-resolution displays, you’re probably a candidate for a Mac Pro.

One other thing to consider is that LCD-backlit displays should be able to last longer than the previous generation of displays, which used fluorescent bulbs for backlighting. This brings into play the all-in-one versus separate components argument. Based on what third parties are offering now in the way of displays with wide colour gamuts, I think a non-Retina display you purchase today will be obsolete before it is inoperative. Thus, I don’t think there is a long term cost savings in buying a standalone display over an iMac if you need an Art-grade display like we do in our labs. (If the price of a display is more important than factors like gamut and Retina/HiDPI resolution, you probably skipped reading most of this section because an iMac offers a value proposition that doesn’t interest you; the new Mac mini should be a great choice for you as I suggested earlier.)


Now that the Mac mini allows a maximum of 64 GB of RAM, it is on par with the 27-inch iMac. The other nice addition is that the RAM is user-upgradeable like it was in the 2012 model. Like the 2012 model, there are 2 slots. It is unclear whether the 8 GB configuration will ship with 2 x 4 GB or 1 x 8 GB, but if it turns out to be the latter, third-party RAM purchases are going to be the way to go to increase your RAM. One vendor is even offering a trade-in credit if you buy a pair, anticipating that Apple will fill both slots. The performance on the Mac mini RAM will be a little better than on the current iMac, but the 27-inch iMac has 4 RAM slots. Again, this is basically a wash, with a fractional edge to the 27-inch iMac because of the 4 slots.


Earlier, I mentioned the comparison between the port configurations between the new Mac mini and the current iMac. For my Lab Macs, 2 Type-A USB ports are not enough right now. We have an alphanumeric keyboard and a MIDI (music) keyboard attached to each station via USB, and some stations have a scanner as well. Users working with video need to be able to use their own storage for large files and we still want to support USB sticks to allow users to transfer or backup files. While we think having those Thunderbolt 3 ports will be beneficial in the long run, in the short to medium term, it will require adapters and/or hubs, which will be hard to keep from walking away in a Lab situation. Speaking of walking away, all iMac models have a Kensington Lock slot, which makes basic physical security easy. For our existing Mac mini computers, we secure each of them with a Tryten Mac mini Security Mount, which then allows a Kensington-style lock to be used.

In both the iMac and the Mac mini, the ports are on the back of the computer. The difference for us in a lab situation is that the iMac ports are meant to be seen and used. On the Mac mini, it is less so. At home, I have one USB hub to deal with a shortage of USB ports and a second one that basically works as an extension cable to bring a USB 3.0 port into comfortable range. In my lab that already supports the Mac mini, we have a custom-built breakout box with a headphone jack (since music courses need easy access) and a USB port[2] to make the ports user-facing, keeping hands away from power, network, and other USB cables.[3] For each existing iMac we might want to replace with a Mac mini, we would want to build such a breakout box (or specifically choose a display that could provide that functionality). So there is a short term cost to a Mac mini deployment in a lab situation that an iMac does not require in most instances.


It appears as if the current iMac will be the last Mac that Apple sells with a “spinning rust” internal hard drive. From here on out, solid state storage is the future on the platform. It’s unfortunate from an upgradeability point of view that the new Mac mini has storage that is soldered into place and cannot be upgraded—a flip from the 2014 model, where the RAM was soldered on and the storage drive(s) could be replaced (albeit with significant effort). Also, recent testing has shown that the new Apple File System (APFS) runs rather slowly on hard drives, so I’m not certain it’s wise for anyone to buy an iMac with an internal hard drive anymore. While you can technically replace the drives on the current iMac, it requires popping the screen off and doing other things that only a repair technician usually does. I think most people will want to opt for at least 256 GB in solid state storage, but you will almost certainly need more if you are working with large media files (including digital instrument libraries and loops that come with apps like Logic Pro X, or standalone collections like Native Instruments Komplete). The only uses I see for the base 128 GB model in our environment might be as a content caching device (formerly caching server) or as a FileMaker Server (since our databases are quite small).


In an ideal world, I’d obtain/access one current iMac and one new Mac mini and start testing, as that is the only sure way to determine what best suits our specific needs. But my reality doesn’t meet that standard. So every conclusion I have drawn here is based on published specs and previous experience. Based on my best reading of that information, the new Mac mini has many good use cases, but the current 27-inch iMac is still a better bang for your buck. I’m hoping to deploy both over the next year or two.

P.S.: I want to thank those who participated in the discussion in the #macadmpodcast channel of the MacAdmins Slack on the topic of the new Mac mini, inspired by Episode 101 of the Mac Admins Podcast. I realized I had more to say—and more to learn—based on that discussion. For situations that are not quite like mine, there are some interesting perspectives in that discussion (and some that might point you in a different direction).

[1] While you can now opt for an external GPU, that would be a difficult choice for my lab environment—one more thing to lock down. For a home computer, that would be a way to mitigate a performance problem after the fact or make that setup with a matte display get iMac-like performance. [Return to main text]

[2] The breakout box was built with FireWire 400 and USB 2.0. Since the company that made the USB hardware has not made a USB 3.0-compatible port, we now have a separate extension cable. So we’ve kept the concept the same, but have had to vary our execution as time has gone on. This particular breakout box is rack mounted, so it is very unlikely to walk away. [Return to main text]

[3] For our large lab, which consists of Mac mini and Mac Pro computers, we keep an SD Card reader on hand for users to borrow rather than try to expose the card reader on the back of the Mac mini. Since this card reader is gone in the 2018 model, nothing will change for us. While the iMac has an exposed SD card reader, I also expect that to go away in the next iMac release, so I did not consider this to be worth raising in this part of the comparison, even though out lab users would need it more than most. [Return to main text]