Apple 27in iMac with Retina 5K display (2017)
Kaby Lake internals, a faster Fusion drive and better graphics give the 5K iMac a timely speed boost
Any other manufacturer would have been accused of flogging a dead horse by now. Another year has rolled by without a significant change to the design of the iMac and yet it remains, categorically, the best-looking all-in-one computer ever made. While we will see the iMac Pro debut later this year, this update is all about incremental improvements.
That’s fine by me. Even after three years, I only have two gripes with the iMac’s design. The first is that there’s no height adjustability: you can only tilt the iMac back and forth. The second is the 27mm-wide bezels surrounding the screen. In 2017 these are starting to look chubby.
Display boost
The Retina display on the original model was already superb and there are still very few 5K monitors that you can go out and buy. Despite this, Apple has improved the screen yet again, boosting maximum brightness by a claimed 43% to build on what was already a stunning display. As with the previous model, the new 5K iMac can reproduce not only the sRGB colour space with incredible accuracy, but also the wider DCI-P3 gamut.
Forget about the intricacies for a moment, though, and you can summarise the iMac’s display like this: it’s bright, insanely crisp and whether you’re dabbling in Photoshop, Final Cut Pro or just shooting everything in sight in BioShock Infinite, it looks stupendous. Blacks look very black; whites look very white. Cute kittens look very cute.
The raw numbers back this up. Our X-Rite i1Display Pro colorimeter is a harsh mistress, capable of revealing the shortcomings that all but the best-trained eyes would struggle to see, but the Retina display puts up quite the fight. Brightness rises from a slightly silly 466cd/m² to an even more outlandish 527cd/m2 (the kind of figures I’d expect from a top-notch TV, not a desktop monitor) and contrast hits a ratio of 960:1, which is very good indeed.
Colour accuracy is fabulous. The last model we reviewed hit an average Delta E of 0.7 and, while this year’s is slightly worse at 0.97, that’s still a terrific result. The panel whips up 98.9% of the DCI-P3 gamut, bar the most intense shades of magenta and blue. The bad news: if you fancy plugging in your MacBook and using the iMac as a 5K monitor, you can’t. Apple still doesn’t support Target Display mode on the 27in iMac, despite adding Thunderbolt 3 support via a pair of USB-C ports on the rear of the machine.
“You can summarise the iMac’s display like this: it’s bright, insanely crisp and looks stupendous in Photoshop or games”
The 9% factor
If you were inquisitive enough to rip open the iMac then you’d find a completely revamped set of innards. Inside, quad-core Intel Kaby Lake processors have been introduced next to a selection of new AMD Radeon Pro graphics chips; the combination delivers a significant speed boost.
It’s not night-and-day stuff, but the changes are welcome. The quad-core 3.4GHz Intel Core i5-7500 in our review model is the slowest chip available in the range, with other choices including the 3.5GHz Core i5-7600 (starting at £1,949), the 3.8GHz Core i5-7600K (also starting at £1,949) and the 4.2GHz Core i7-7700K (from £2,219). Memory is available in 8GB, 16GB, 32GB or 64GB portions; our test iMac came with 8GB.
In our in-house benchmarks the 3.4GHz model turned out to be quicker than the 3.2GHz Core i5 Skylake model we tested back in 2015 by a margin of 9%, which is similar to the improvement that model delivered over 2014’s version. In all honesty, it isn’t a huge performance boost; certainly not big enough to notice in everyday use.
Graphics performance, though, has seen a bigger improvement. This year, depending on the model, you’ll get either an AMD Radeon Pro 570, Pro 575 or Pro 580, and the difference over 2015’s 27in 5K iMac is significant.
I’ve only had the chance to test the AMD Radeon Pro 570-equipped model, which is in the lowest-spec 5K iMac this year, but with results that beat the last edition’s top-end model – and by quite a distance – it’s a major step forwards.
Whether you’ll be able to game smoothly at the screen’s native 5K resolution is another matter entirely. I put the iMac through its paces using Unigine’s Heaven Benchmark – a good representation of how much gaming grunt a machine has – and it reveals that, although much faster than before, the iMac’s GPU power is still limited.
At 2,560 x 1,440 resolution and Medium detail, the Pro 570 in our review unit achieved a mostly smooth
42fps, which is double that of the 2015 iMac’s 26fps. If that sounds promising, remember that this test still isn’t running at the full 5,120 x 2,880 the display is capable of; the benchmark simply doesn’t run at such high resolutions.
Our review iMac included a 1TB Fusion drive, with the top-end model available with a 2TB or 3TB disk. Sadly, it’s not nuclear-powered – this would be simultaneously worrying and impressive – but it does combine a super-fast SSD with an old-school hard disk.
The theory is that all your regularly used applications and data end up on the SSD, and everything else is plonked onto the hard disk. There isn’t much change to the amount of SSD storage on offer here, though, with this year’s 1TB drive including 32GB of fast flash storage compared to the 2015 model’s 24GB. If you want to get back up to the 128GB flash storage that was offered on the original iMac 5K’s Fusion Drive, you’ll have to move up to the 2TB or 3TB model.
Does the Fusion Drive work, though? It is quick in benchmarks, but it’s difficult to say how well the system will work once you’ve filled the storage with the accumulated gunk of several year’s use. Out of the box, I clocked it at 987MB/sec while reading files, and 130MB/sec writing them back to the disk. That’s faster for reads than the previous model, although a touch slower for writes.
This is nowhere near as lightningfast as the pure flash storage in the latest MacBook Pro laptops, however. If that sort of performance is paramount, then you can swap to an SSD-only iMac, with 256GB, 512GB and 1TB options available on the Core i5 5K iMac and a huge 2TB SSD drive available on the top-end Core i7. Bear in mind, though, that all these add cost over the 1TB Fusion Drive, with the 2TB SSD increasing the price by £1,260.
Magic peripherals
While not genuinely magic, Apple’s accessories are pretty special. The Magic Trackpad 2 is the same offering as last time out, but that’s no bad thing. It has the air of a Philippe Starck-designed door wedge and is more expensive than ever at £144. If you’d rather have your magic in Touchpad than mouse form, you can swap it for £50 when you buy it with your iMac. Want both a mouse and a trackpad? That’ll be a further £129.
It’s still a wonderful thing, though, with a 30% larger touch surface than its predecessor and Force Touch providing that extra layer of luxury. Powered-off, it’s a large slab of cold, unclicky frosted glass, but flick the switch and it provides all the handy Force Touch functionality and gesture-controlled loveliness I’ve come to expect from my MacBook Pro.
Touchpads on a desktop might sound like a rubbish idea, but Apple really makes it work – flicking between multiple desktops and whizzing up Mission Control is super, super fast and instinctive. Plug it in, use it, and – trust me – you’ll miss it when it’s gone. The coolest feature? Silent Clicking. Enable this in the control panel and the high-pitched click disappears, leaving only the low-frequency thump to be felt through your fingertip.
It’s harder to get excited about the Magic Keyboard. It’s flat, due to the removal of the AA battery compartment from the old Magic Keyboard, so depending on how you like your keyboard to be angled this may not be your bag at all. There is, however, at long last, an extended version of the keyboard with a numeric pad stuck on the side. Yours for another £30. Are you keeping tally?
Whichever model of keyboard you choose, it’s as nice to type on as the previous model. The function keys along the top are now all full-size, and the left and right cursor keys have grown slightly.
Magic Mouse 2? It’s a mouse. It’s wireless. It moves cursors all day, every day. It’s comfy to use, and although there still aren’t discrete left and right buttons, it works so predictably that there may as well be. It’s also rechargeable, with the AA batteries of the original flung out in favour of a lithium-ion battery.
Tasty ports
The iMac has some tasty ports; that’s the good news. The bad: they’re all hidden around the right-hand rear of the iMac, so plugging in a USB device involves far too much getting up, leaning and generally moving around for my liking.
When you peer round the back, you’ll see four USB 3 ports, one Gigabit Ethernet, an SD card reader and a headphone output that doubles as an optical digital audio out. There are a couple of new ports here too, with a pair of Thunderbolt 3 USB-C ports supplanting the Thunderbolt 2 ports of old, doubling potential data transfers from 20Gbits/sec to 40Gbits/ sec and opening the way for external graphics acceleration once macOS High Sierra arrives later in the year.
Factor in 802.11ac and the iMac hits all the right notes. You can even whip off a panel at the rear and add more RAM. There are four slots, with two occupied as standard and you should be able to add up to 64GB. Note that you’ll probaly want to do this yourself: Apple charges a crazy £180 to upgrade from 8GB to 16GB of RAM on the base model.
Verdict
So let’s assume you want to buy one. Which do you choose? In a way, this is an easy question: any of them. Even the base model 5K iMac, no longer hobbled by a non-Fusion Drive hard disk, will suffice. While it’s impossible to describe any computer that costs £1,749 as cheap, it still represents great value for money. A display of this quality would cost at least £1,000 on its own, maybe more, and it wouldn’t be as pretty or come with a fast, capable, fully functioning computer inside. It’s a just a shame that Apple charges such silly prices for upgrades that many people will view as essential. SPECIFICATIONS Quad-core 3.4GHz Core i5-7500 processor AMD Radeon Pro 570 with 4GB of VRAM 8GB DDR4 RAM 1TB Fusion Drive 27in 5,120 x 2,880 Retina 5K IPS display SDXC card slot 4 x USB 3 2 x Thunderbolt 3/USB-C Gigabit Ethernet 802.11ac Wi-Fi Bluetooth 4.2 FaceTime HD camera macOS Sierra Magic Mouse 2 Magic Keyboard 1yr RTB warranty 650 x 203 x 516mm (WDH) 9.4kg
“It’s just a shame that Apple charges such silly prices for upgrades that many people will view as essential”