Retina iMac vs. Mac Pro: Which Mac powerhouse should you get?

9th January 2015
Group project work on an Apple desktop

Apple recently introduced the Retina iMac, which marked the first time a desktop Macintosh had received the full “Retina” treatment capable of displaying 5K resolution. With that many pixels on the screen and with more than enough power under the hood to make those pixels do magical things, you may be wondering whether the Retina iMac or a new Mac Pro would be a better choice.

Retina iMac

First of all, there’s that display: 5120 x 2880 resolution – twice the horizontal resolution and twice the vertical resolution as other 27-inch iMac models.  So, that’s 14.7 million pixels in total; so many in fact, that Apple had to develop its own custom timing controller to get the screen to work right.
The 5K display is aimed at content creators and others working with truly high-definition, high-resolution source material. You can edit a 4K movie on the Retina iMac at full resolution using Final Cut Pro, for example, and still have enough space left over to see tools, timeline and clips.
The Retina iMac is also Apple’s fastest iMac model. It sports a 3.5 GHz quad-core Intel Core i5 processor, paired to AMD Radeon R9 M290X graphics. It comes with 8 GB RAM and a 1 TB Fusion Drive. The iMac includes four USB 3.0 ports, two Thunderbolt2 ports, Gigabit Ethernet, headphone port and SDXC card slot. Bluetooth 4.0 and 802.11ac Wi-Fi are also built in.
You can specify options to ‘pimp’ your iMac to within an inch of its life, with order options including gaining more memory, faster Core i7 processor, faster graphics, and different storage options, including a 3 TB Fusion Drive and pure SSD Flash storage up to 1 TB.

Mac Pro

The latest design of the Mac Pro began shipping shortly before the end of 2013 and it’s a very different computer than the iMac. The Mac Pro has been built from the ground up, and its three main goals are speed, speed and a little bit more speed. With the exception of the fans, there are no moving parts inside: Everything is solid state. The system comes equipped with Flash storage only, so there’s no internal hard disk drive.
It’s shaped like a turbine, and it is “headless” – meaning it has no built-in keyboard or display. The turbine shape was designed to repel heat from a unified thermal core; inside the Mac Pro, most of the major heat-generating components face inward, so whisper-quiet fans draw cool air through the base and expel warm air out through the top to keep things cool. On the back of the Mac Pro, you’ll find four USB 3 ports, six Thunderbolt 2 ports, two Gigabit Ethernet connectors, an HDMI port, combined optical digital audio output/analogue line out mini jack and headphone jack. Bluetooth 4.0 and 802.11ac Wi-Fi are included.
The Mac Pro comes in two configurations: a 3.7 GHz 4-core system with 12 GB RAM and dual AMD D300 graphics processors, and a 3.5 GHz 6-core system with 16 GB RAM and dual AMD D500 graphics processors for an extra $1k (£658). Both come as standard with 256 GB of Flash storage.
Order options include upgrades to an 8 or 12-core processor; memory increments up to 64 GB RAM and up to 1 TB of flash storage; and dual AMD D700 graphics processors.
No clear winner there, so let’s take a look at the individual specs that matter.


In simple terms, this is an easy one – the Retina iMac wins hands down, mainly because the Mac Pro doesn’t ship with a display (or a keyboard) but does have more ports to connect a display to than you can shake a stick at!
The Retina iMac’s 5K screen is the biggest display in the Mac world: 14.7 million pixels, four times the size of the other 27-inch iMac screens. And it’s simply gorgeous with its deep blacks, bright colours and sharp contrast. Even small typography is readable on the screen — more like looking at print than seeing a monitor. It truly is a thing of beauty.
However, with a plethora of PC’s coming onto the market with 4K displays, the Retina iMac could metaphorically be compared with speakers that go up to 11 (i.e. you wonder whether the difference between a 4k and a 5K display will be noticeable in the real world). But history provides the answer, as we have been there before with iPad vs. Retina iPad, and I don’t know anyone with a Retina iPad that would go back to a non-retina version willingly.
The Mac Pro doesn’t have a built-in screen, but it does have plenty more expansion ports. There are a total of six Thunderbolt 2 ports on the Mac Pro, three times as many as the Retina iMac, and each of them can be used to drive a Thunderbolt Display. There’s also an HDMI 1.4 interface, which can connect a 4K television. You can have a total of six external screens connected to the Mac Pro at once, working at standard resolution (defined as the 2560 x 1440 resolution of a Thunderbolt Display). If you work in 4K, you can have three 4K displays hooked up to the Mac Pro instead.
That does mean, however, that if you buy the Apple branded Thunderbolt displays you’ll be spending more on external displays for your Mac Pro than you would be on a Retina iMac. But this isn’t about budget; it’s about what is best!
Of course, the Retina iMac also has expansion ports that you could use for additional displays, but we can call this one a draw overall. If you want a single stunning display then the iMac’s internal 5K display really sets it apart from any other Mac right now, and it’s absolutely worth checking out. But if your requirement is for multiple monitors, then the Mac Pro should be your weapon of choice.


Like most of the other iMacs, the Retina iMac comes equipped with an Intel Core processor. This one is the quad-core i5 chip, but it’s a bit faster than some of the others iMacs at 3.5 GHz. If you prefer, you can spend more for an even faster 4.0 GHz Intel Core i7 processor.
The base model Mac Pro is a bit faster. It uses a 3.7 GHz quad-core processor – though Apple opted to use Intel’s Xeon E5 processor for the Mac Pro instead. The Xeon E5 is a heavier-duty processor aimed at server operations.
Xeon chips are designed to run cooler at high load, and they also support a special type of memory called Error Correcting Code (ECC) that’s better for computational operations where you can’t afford any sort of error (scientific work, for example). They also have huge amounts of L3 cache, which can greatly speed up operations.
Both standard processors are quad-core, meaning that for an application making use of multithreading technology the processor is capable of doing four times the work. This encompasses a large percentage of what your machine does in the course of a day. The more cores the Mac has, the more efficiently it can perform tasks that are optimised for this sort of CPU.
Real world examples of this include encoding video, compressing/decompressing files and compiling code. Parallel processing is so integral to OS X that Apple developed a core technology built into OS X called Grand Central Dispatch, which it uses to manage its multiprocessing operations as efficiently as possible.
The Mac Pro comes in two basic configurations: One has a quad-core Xeon processor, while the other has a six-core Xeon processor. If parallel processing performance is important to you, you can upgrade to an eight-core processor, or even take the Mac Pro up to 12 cores. Obviously, clock speed goes down as you start piling on more cores (each of the 12 cores would run at around 2.7GHz) but the assumption is that you can get more done if you’re using multithreaded apps.
In the end, these are two thoroughly different classes of computer. The iMac’s standard processor is incredibly powerful, but the Mac Pro is a parallel processing monster that’s designed for more specialised work than the iMac.


At first glance, the Mac Pro and the Retina iMac both come with graphics processors manufactured by AMD, but dig a little bit deeper and they’re very different. While both are powerful, the Retina iMac is squarely a consumer-class product. The Mac Pro is a workstation processor – well, dual workstation processors, more specifically.
The Retina iMac contains AMD’s Radeon R9 M290X, which is – rather surprisingly due to its lush 5K display – actually a mobile Graphics Processor!  Though this juxtaposition of a 5K display and a mobile GPU doesn’t seem to make sense at first, it is AMD’s top-of-the-line mobile graphics processor. Aimed at consumers looking for the best possible performance and experience out of their system, it is aligned with a bunch of exciting technology that make this an extremely capable performer.
The Mac Pro touts AMD’s FirePro D300, D500 or D700 graphics processors, depending on configuration, and not just one, but two. FirePro graphics aren’t aimed at consumers — they’re workstation graphics cards. They can handle digital video editing at 4K while applying visual effects, for example, or manipulating huge 3D models.
What’s more, FirePro graphics are designed for more than just general use — they’re also parallel-processing pipelines. For apps that use OpenCL — data visualisation tools, tools used in science and research — the FirePro graphics chips can be a tremendous boost.
There’s no question that the Mac Pro has more powerful and more flexible graphics processing units than the iMac, but just as with the CPU, both systems are custom tailored to different uses. For example, OS X gaming on the Retina iMac would be a better choice than on the Mac Pro (despite the latter having 2 GPU’s OS X can only use one of them to render games).


The Retina iMac comes with a 1 TB Fusion Drive. The Fusion Drive combines a 128 GB PCI Express-based Flash drive with a 1 TB hard disk drive; they’re linked together to create one logical volume meaning much quicker boot speeds, application launching and document loading than a hard drive alone.
If 1 TB isn’t enough, you can upgrade it to a 3 TB Fusion Drive. You can also go pure SSD if you want, up to 1 TB of flash storage in total.
Speaking of pure SSD, that’s all you’ll find on the Mac Pro. The Mac Pro’s only moving part is its fan. Oddly, you can’t configure it with anything close to the capacity of the Mac mini – 1 TB is as large as it gets inside. Apple says that’s not that big a deal because of all the Thunderbolt 2 ports, but that’s a bit like buying a sports car and using it to tow a caravan, methinks?

Who should buy the Retina 5K iMac?

The Retina iMac is a stunning piece of engineering. It’s sleek, fast, and has the best-looking display of any Mac in circulation. Under the hood it has the right balance of power and performance for anything you can throw at it, whether it’s editing video in 4K, editing photos, playing a video game or just working in Microsoft Office or iWork.
The first Mac capable of displaying 5K video is in a league of its own right now; a distinct and unique offering that shares the outward trappings of other computers that share its name. It’s not for everyone — most people can spend way less money on an iMac and get an eminently capable computer that will keep up with them no matter what they do.

Who should buy the Mac Pro?

Apple aims the Mac Pro squarely at the same sort of digital content creators who can benefit from the iMac: People working with digital video (4K or otherwise), digital audio engineering, Photoshop or other image editing software – essentially all of the traditional strengths of the Mac platform.
The Mac Pro has plenty of applications beyond that, though. It’s a fantastic machine for engineers, architects and others working with 3D visualisation and design. Its parallel processing-optimised architecture also makes it superb for scientific work too.
The Mac Pro may not be able to display a 5K image, but it can run multiple 4K displays or even more lower-resolution monitors like Apple’s Thunderbolt Display. In conjunction with its all solid-state design, and processor and GPU options that can take its performance to the stratosphere, the Mac Pro is a formidable option for anyone.
Of course, all this power comes at a price. The base Mac Pro is a few hundred £’s more than the Retina iMac, but when customising it with the fastest processors, a whack of additional storage, loads of RAM and a better GPU, you can triple the base price quite easily!
For the user who absolutely wants performance without compromise, the Mac Pro is the machine to get. If you want the fastest, most capable iMac on the block then the Retina iMac is hugely competent, and what you potentially lose in performance, you also lose on the price tag.

Still undecided?

Regardless of whether you choose a Retina iMac or a Mac Pro, you can be safe in the knowledge that HardSoft’s lease agreements allow for effective budgeting and avoiding compromising any existing bank credit lines. This frees up finance to input into other areas of your business that need it. Easy leasing comes with a 3 year warranty (i.e. the entirety of the lease agreement) and if something goes wrong that isn’t a fault of your own, we will sort it for you. All leases also come with unlimited telephone support where you can speak to one of our Apple Certified technicians. Our own trained engineers are also available to visit you on site if necessary.
Hopefully this breakdown has given you some food for thought and has answered some questions. If you need further help, feel free to ask. We like to help. It’s what we are here for.