Apple iMac with Retina 5K display: Finally, a Retina display for the desktop

So the rumors were true. Apple recently released a new iMac which comes with a 27-inch display that has a mind-boggling 5120 x 2880 pixels resolution. Do you really need a 5K display? And does it compromise performance? We answer these questions and more in our review.

Pixels be Gone

No one can say for sure who started the trend of high pixel density count displays, but Apple was certainly amongst the first when they launched the iPhone 4 in 2010, which featured the company’s first “Retina display”. And at the beginning of this year, we postulated that 2014 could see the start of a display resolution war between PC manufacturers. True enough, with 4K being one of the key trends of the year, PC manufacturers are putting higher resolution displays especially on notebooks.

As for Apple, the company’s Retina displays soon found their way from their iPhones to their iPads and MacBook Pros, but was conspicuously missing from their iMacs until now. It was long rumored that Apple was working on a new iMac with a Retina display. But what we did not know was what kind of display resolution it would sport. And on the 17th of last month, Apple finally announced that its new iMac would indeed have a Retina display and that its display resolution would be a whopping 5120 x 2880 pixels or 5K.

However, as we all know, having more pixels might mean sharper and crisper images, but it also places additional workload on the system - more pixels requires more processing power to fill them. So how does this new iMac perform and is the 5K Retina display really worth getting? This review seeks to answer these questions and more. But first (no, we are not going to take a selfie), let’s take a look at the hardware bits and design of this new iMac.

 

The Hardware

Here's a screenshot to illustrate the difference between 5K and Full-HD. The image in the top left corner is a Full-HD photo. Look at how much more desktop space there is.

Here's a screenshot to illustrate the difference between 5K and Full-HD. The image in the top left corner is a Full-HD photo. Look at how much more desktop space there is.

We begin with the hardware and the star of the show here is the new 5K Retina display. 5K resolution is 5120 horizontal pixels by 2880 vertical pixels, giving a total pixel count of over 14.7 million. That is a lot of pixels. To give an idea of just how many pixels this is, consider the table below.

Display Standard

Actual Number of Pixels

5K
5120 x 2880 = 14.7 million
4K
3840 x 2160 = 8.3 million
WXQGA
2560 x 1600 = 4.1 million
QHD
2560 x 1440 = 3.7 million
Full-HD
1920 x 1080 = 2.1 million

Quite deceptively, 5K resolution is not just 25% more pixels than 4K - it’s actually almost 80% more! And it also represents seven times more pixels than Full-HD. This also means that content creators working with 4K content can do so in native resolution and still have room for other elements and assets. And as you would expect, the display of this new iMac with Retina 5K display is super sharp. Text and images all look super crisp. Viewing angles are good too. It's a truly gorgeous display that offers great clarity, sharpness and richness. One look at it and no desktop display will ever quite look the same again.

The iMac with Retina 5K display serves up good viewing angles.

The iMac with Retina 5K display serves up good viewing angles.

With so many pixels, Apple needed to design its own timing controller, as there is none currently in production that can handle 5K resolution and the massive amount of bandwidth it requires. To be precise, Apple’s custom timing controller offers up to 40Gbps of bandwidth. Clearly, the new iMac packs lots of pixels. But if we look at the pixel density count of its MacBook Pros with Retina displays, it soon becomes clear why Apple needed to pack so many pixels into its 27-inch iMac.

As you can see, the current generation MacBook Pros with Retina displays have screens that have a pixel density count of around 220 ppi. That’s actually the lowest amongst other Apple products with Retina displays. But the MacBook Pros get away with it because users typically hold their phones and tablets closer to their eyes. As it is, 220 seems to be the magic  number and had Apple decided to go with a 4K display instead of a 5K one (for the same display size), who would then be looking at a pixel density count of just 163 - far below the standard of the current MacBook Pros with Retina display.

To give an idea of the disparity in pixel density, look at the two images below, which have been taken at the roughly the same distance. Although both have been cropped to 800 pixels width, the difference is clear. The top image is a photograph taken from the new iMac with 5K Retina display and the bottom is taken from a typical 23-inch 1080p monitor - a very popular resolution and size amongst users. The iMac has a pixel density of 217.6 pixels per inch while the 23-inch 1080p monitor has a pixel density of just 95.8 per inch - less than half.

To drive such a high resolution display, this new iMac is powered by quad-core Intel Core i5-4690 processor that runs at 3.5GHz (6MB L3 cache) and comes with 8GB of RAM as standard. This Core i5-4690 processor is a mid-range processor and though it has four cores, it does not support Hyper-Threading. For users who demand more, they can opt for a powerful quad-core Core i7-4790K processor that runs at 4GHz (8MB L3 cache) and supports Hyper-Threading, and also upgrade memory to a maximum of 32GB. Storage, in the base model like ours, comes in the form of a 1TB Fusion Drive. For those unfamiliar with Fusion Drive, it debuted with in 2012 when Apple refreshed its iMac design and basically combines a small flash drive with a mechanical hard disk drive so that users get the performance of a flash drive and the capacity of mechanical hard disk drive. We talked about this in greater detail in our review of the 2012 iMac here. Users can also opt for either a 3TB Fusion Drive or 256GB, 512GB or 1TB of SSD storage.

Graphics processing duties are handled by AMD’s Radeon R9 M290X that has 2GB of GDDR5 memory. Again, users demanding more can opt for the more powerful Radeon R9 M295X with 4GB of GDDR5 memory. The choice of AMD graphics has left some users miffed, considering the potency of NVIDIA’s latest GeForce GTX 980M and 970M processors, and the fact that the Radeon R9 M290X is in fact a renamed Radeon HD 8970M, which is in turn based on the old Radeon HD 7870 from 2012. That said, the decision has likely got to do with the fact that Apple needed AMD’s help in developing the custom timing controller in its 5K display. AMD has been known to be an enthusiastic supporter of the DisplayPort interface and has been adept at scaling resolutions for up to five screens simultaneously.

 

The Design

The new iMac with Retina 5K display looks just like any other iMac from 2012 onwards.

The new iMac with Retina 5K display looks just like any other iMac from 2012 onwards.

Apple redesigned the iMac in 2012, and even today it still looks fresh and cutting-edge. There is no real reason to update the design, since the only niggle we have with it is that its stand does not allow for much adjustability - it only tilts and cannot be adjusted for height. And so the new 27-inch iMac with 5K Retina display retains the same design as the models that precedes it.

The stand, while nicely sculpted and elegant in design, allows users to only adjust for tilt and not height.

The stand, while nicely sculpted and elegant in design, allows users to only adjust for tilt and not height.

The edges of the iMac's display is just 5mm thick - thinner than the latest iPhone 6. The bulge in the middle, which houses all the components, is not that thick either.

The edges of the iMac's display is just 5mm thick - thinner than the latest iPhone 6. The bulge in the middle, which houses all the components, is not that thick either.

This means it is superbly slim - the edges of the display measure just 5mm thick. And in case you were wondering, the 5K Retina display itself measures just 1.4mm thick and yet it is made up of 23 layers and a whole host of advanced technologies including a process called photo alignment that uses UV light to ensure that the liquid crystals are properly aligned, and another process known as organic passivation that prevents cross-talk and interference that could occur from having pixels so close to each other.

And thanks to the slim display, this new iMac also does not take up much space. Sure, the 27-inch display is pretty big and measures 65cm across and 51cm tall, but the actual desktop real estate it takes up is not that crazy thanks to the display’s slim dimensions and the fact that the stand only has a depth of around 20cm. Its also fairly easy to carry around since it weighs just under 10kg.

From left to right users will find a headphones jack, SDXC card reader, quadruple USB 3.0 ports, dual Thunderbolt 2 ports and a Gigabit Ethernet port.

From left to right users will find a headphones jack, SDXC card reader, quadruple USB 3.0 ports, dual Thunderbolt 2 ports and a Gigabit Ethernet port.

Round the back, users will notice that the iMac bulges towards the middle of the display, which is typical because that it where all the components are. As for ports, this new iMac retains the same configurations as the other iMac models with the exception of newer Thunderbolt 2 ports. Physically, Thunderbolt 2 and Thunderbolt 1 are similar, except that the former can now combine the two previously separate 10Gbps channels into a single 20Gbps channel, this gives it greater flexibility and ability. For instance, Thunderbolt 2 can now support 4K displays, which was previously impossible due to the bandwidth demands of driving a 4K display, which is around 15Gbps (greater than that of a single 10Gbps channel of Thunderbolt 1).

Despite the high bandwidth supported by the Thunderbolt 2 interface, it must be noted that users will be not be able to use the iMac with Retina 5K display in Target Display Mode - remember, the timing controller used in the device offers 40Gbps of bandwidth. Thunderbolt 2 offers 40Gbps of bandwidth, but a single device can only use up to 20Gbps, which is insufficient for transmitting 5K video signals.

Performance Benchmarking

To evaluate the new iMac with Retina 5K display, we will be measuring its Geekbench scores against some of the more recent Mac systems that we have tested - a Late 2013 27-inch iMac and 15-inch MacBook Pro as well as the recently released “entry-level” 21.5-inch iMac. That aside, we will also pit the iMac with 5K Retina display against some recently tested AIO systems, Mini-PC systems and gaming notebooks. An interesting thing to note is when running in Windows, the iMac with Retina 5K display will only support a maximum resolution of 3840 x 2160 pixels or 4K. Since this is the only 5K display in the market today, this is likely due to the fact that AMD has yet to release graphics drivers that will handle 5K resolution.

The full list of benchmarks used are as follows:

  • Geekbench 3.1.5
  • PCMark 8
  • 3DMark 2013
  • Tomb Raider
  • Crysis 2

 

Geekbench 3.1.5

Geekbench is a popular Mac OS X benchmarking tool and it runs a variety of tests that taxes individual components of a system such as the processor and memory and then gives an overall score of the system’s performance.

The new iMac with Retina 5K display put up a respectable showing, but was outperformed in by the Late 2013 iMac and MacBook Pro in the Multi Core tests. This is because the Core i5-4690 processor in the new iMac lacks Hyper-Threading. So for users who rely heavily on programs that can take advantage of Hyper-Threading, it might be worth upgrading to the more powerful Core i7-4790K processor.

 

 

PCMark 8

PCMark 8 is the latest benchmarking utility from Futuremark and was designed to measure the performance of Windows 8 systems. We will be testing the system using four different scenarios, Home, Creative, Work and Storage, which simulates different workloads that a user might subject the system to. We then topped it up with two more application test scenarios that use the full suite of Microsoft Office applications and another using Adobe's Creative Suite 6.

On PCMark 8, the new iMac with Retina 5K display recorded decent scores in the “Home”, “Creative” and “Work” test scenarios, which attests to its fairly powerful quad-core Core i5-4690 processor, 8GB of memory and beefy AMD R9 M290X GPU. However, its number dipped when it came to “Storage” because Windows cannot take advantage of its Fusion Drive - in Windows, the Fusion Drive works just like any other mechanical hard disk drive. This also led to its poor scores in the following two “Apps” test scenarios which usually require heave use of the storage subsystem.

3DMark 2013

The AMD R9 M290X GPU might be based on an old GPU design, but it still remains to be one of AMD’s most powerful mobile GPUs and the results on 3DMark 2013 clearly show that. It easily outscored our Late 2013 MacBook Pro, which is powered by a mid-range NVIDIA GeForce GT 750M; and even the Aftershock XG13, which has a more powerful gaming-grade NVIDIA GeForce GTX 860M.  

Crysis 2

Seeing that the system’s performance was so encouraging on 3DMark 2013, we decided to compare its scores in our gaming benchmarks with bona fide gaming notebooks. On Crysis 2, the iMac with Retina 5K display did well and managed almost 60fps on “Very High” settings even at Full-HD resolution. However, we noticed that performance dipped substantially when we increased the graphics settings to “Ultra”. And as expected, gaming on 4K is just not ideal. Even on “Normal” settings, the system achieved just 23fps, well below the playable threshold of 30fps.

 

Tomb Raider

Tomb Raider is a less demanding game and the numbers reflect that. On Full-HD resolution, the new iMac with Retina 5K display recorded very good frame rates even at “High” graphics settings. However, turning the resolution up to 4K drastically reduced frame rates. At 4K resolution and “Normal” graphics settings, Tomb Raider was barely playable. Compared to the other gaming notebooks, the iMac’s performance was actually pretty decent and competitive.

 

Simply Gorgeous

The short story is this: this new iMac with Retina 5K display is simply gorgeous. If you have been spoilt by the high pixel density displays of leading smartphones and you want a desktop equivalent, this iMac is it. It is considerably pricier, but we feel that its awesome 5K display justifies its premium.

From a performance standpoint, the new iMac is an able performer. Admittedly, the default Intel Core i5-4690 processor, AMD R9 M290X mobile GPU and Fusion Drive is not the most bleeding edge of what technology has to offer now, but it gets the job done well enough while keeping costs down. Besides, for more demanding users, Apple has offered upgrades which will surely bring the iMac on to another level of performance. Though this will come at a cost of a pretty penny.

Cost is an important consideration, because the only other 5K display available right now comes from Dell and that is rumored to be available later this year at the cost of around US$2,500. That is the same as what Apple is asking for their base configuration iMac with Retina 5K display. If you were to compare the two, the iMac is an absolute steal then. The base configuration iMac retails for S$3,388 locally.

As it is, if you are a mainstream user shopping for an iMac and have cash to splash, this new iMac with Retina 5K display is the obvious choice. The display is simply stunning to behold and the machine is speedy and snappy to use for everyday computing tasks. No longer do you need to deal with the display disparity between your smartphone and your desktop.

This advice is also true if you are professional photo or video editor as the extra pixels will surely help with your work. For video professionals, this new iMac will make it possible to edit 4K videos in their native resolution and still have space for other elements and assets such as your editing toolbars.

Unfortunately, some professionals might find the base configurations lacking in their requirements and it is important to note that, like all other Apple products, selecting optional components such as a more powerful processor and GPU can increase cost tremendously. The Core i7 processor upgrade costs an additional S$350; whereas maxing the memory to 32GB will set you back S$850; the AMD R9 M295X GPU requires an extra S$350; and if you want a 1TB SSD, that’s a whopping S$1,120 extra. So if you do opt to upgrade everything, the final cost is an eye-watering S$5,698. Go easy on the upgrades, then.

The display on the new iMac with Retina 5K display is gorgeous, but it is not an iMac for everyone.

The display on the new iMac with Retina 5K display is gorgeous, but it is not an iMac for everyone.

Upgrades aside, this new iMac is not without its foibles. The 5K Retina display is a double-edged sword. Mostly it is because there is not that much high-resolution content out there that can truly take advantage of the display. And upscaling content does introduce a bit of fuzziness, though it is only apparent if you really come close to the screen and squint.

Additionally, if you do play games on OS X, the AMD graphics simply does not have the horsepower to drive games at its full native 5K resolution. Again, you would have to play at a lower resolution and upscale the image to fit the screen. For sticklers, this is obviously not the most ideal solution, but gaming at 5K resolution is simply too much to ask from any mobile GPU right now. The only other option is to have a separate lower resolution display just for gaming, but surely this is just ridiculous right? This new iMac is just not that great for games, despite the rather powerful GPU.

To end, the iMac with Retina 5K display can be seen as a herald of things to come. Ultra-high resolution displays will continue to be popular and there are convincing reasons to get one. However, technology still needs catching up to do to be able to drive these displays for all purposes and not just for productivity and everyday computing applications.

Our articles may contain affiliate links. If you buy through these links, we may earn a small commission.

Share this article