Review: 21-inch Apple iMac

Introduction

Less than a year after the chassis overhaul that gave the iMac its new slimline bodywork, Apple's innovative desktop computer enjoys another revision.

This time, it's a minor refresh, bringing Haswell processors, better GPUs and faster WiFi, but retaining the form factor of the previous generation. It's an unsurprising move.

Last year's update had already radically redesigned the all-in-one Mac, dropping the optical drive in favour of a new slimline design with better speakers, a revamped and less reflective screen construction, USB 3.0 ports and a second Thunderbolt port.

The upgrades for this year's model are all internal. If you were hoping for a Retina display, you'll be disappointed.

Naturally, the iMac isn't the only slimline all-in-one computer out there. The Scan 3XS Mirage AIO245 costs over £1,000 (about US$1,600, AU$1,600) for the entry-level model, which is not much cheaper than the cheapest 21-inch iMac, but it features a larger 23.46-inch screen and a wide range of configuration options.

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• New Mac Pro

Lenovo's IdeaCentre B540p starts at around £600 (about US$1,000, AU$1,000). It has a 23-inch touchscreen panel and 3D capabilities. The Acer Aspire 5600U costs a little more at just over £750 (about US$1,200, AU$1,200), but it's a great family media centre, and the Asus Transformer AiO P1801is a hybrid tablet and desktop with two separate processors, one running Windows 8 and one running Android 4.1 Jelly Bean. For £600 (about US$1,000, AU$1,000), you could buy a Lenovo ThinkCentre M92p Tiny. It's not an all-in-one, but the PC is extremely small.

If you prefer to stick with a Mac, Apple's other desktop option is the Mac mini. This small form factor machine is the cheapest way to own a Mac, though it doesn't come supplied with a display, a keyboard or a mouse. The top-of-the-range Mac Pro isn't currently on sale in Europe and is about to be overhauled with a new release, so now is not the best time to invest in one.

As the new iMacs share the previous generation's form factor, they also suffer from the same limitations. As mentioned before, there's no optical drive, so if you want to use DVDs and CDs, you need an external model such as Apple's own USB Super Drive.

Upgradeability is also a problem. On these 21.5-inch models reviewed here, you can't add memory yourself, though a configuration option is available if you order from the Apple Online Store. Also, as the screen is glued in place instead of held by magnets, it's more difficult for even specialists to access the internal components.

Features

As you'd expect, the new late 2013 iMac comes in four configurations, the two 21.5-inch models reviewed here, and two 27-inch versions. The 21.5-inch iMacs cost £1,149 (about US$1,850, AU$1,900) and £1,299 (US$2,100, AU$2,160) respectively, both somewhat more expensive than their 2012 counterpart.

Their processors have the same clock speeds as before, at 2.7GHz for the cheaper one and 2.9GHz for the more expensive, and they're still Intel quad core Core i5s, with an upgrade option for a 3.1GHz Core i7 chip for the more expensive 21.5-inch iMac only.

At times of high processing needs, the CPUs can Turbo Boost up to 3.2GHz and 3.6GHz respectively, though the quad core Core i5 chip doesn't have Hyper Threading, whereby each of its cores can run two threads. If this feature is important to you, go for the Core i7 upgrade option, which can run two threads on each of its four cores, giving eight virtual threads.

For graphics, the higher-specced 21.5-inch iMac has an Nvidia GeForce GT 750M with 1GB RAM, which is up from the Nvidia GeForce GT 650M used last year. The entry-level model, however, drops the discrete graphics chip altogether, and relies on the new Haswell processor's integrated Intel Iris Pro 5200 graphics.

While integrated graphics chipsets share memory with the CPU, Iris Pro also adds 128MB of DRAM for extra memory bandwidth. We're promised it will at least match the GeForce GT 640M used last year.

Both of the new 21.5-inch iMacs have 8GB of 1600MHz DDR3 memory, which is a generous allowance, but as mentioned before, it's not user upgradeable. If you think you need more, best use the online custom option and increase it to 16GB for an extra £160 (about US$260, AU$270).

Both models also have a 1TB hard drive out of the box. Unfortunately, they're 5,400rpm, unlike the 27-inch iMacs that have faster 7,200rpm hard drives. Storage can be upgraded to a Fusion Drive, which combines a 1TB hard drive with flash storage, or a solid state drive of 256GB or 512GB capacity.

Both 21.5-inch releases are now WiFi ac, giving up to three times as fast wireless connectivity when used with a compatible router, and both offer Bluetooth 4.0.

For peripherals, there's two Thunderbolt ports, four USB 3.0 ports, gigabit Ethernet and an SDXC card reader slot. Both come with the latest version of OS X installed (10.8: Mountain Lion at the time of writing, but they'll be upgraded to 10.9: Mavericks as soon as it's released).

Apple's respected lifestyle suite iLife is also bundled, including iPhoto, GarageBand and iMovie. All iMacs come with a wireless keyboard and a Magic Mouse, but if you order online, you can swap them for a USB keyboard with a numeric keypad and a Magic Trackpad respectively at no extra cost.

Performance

Benchmarks

iMac 21.5-inch, 2.7GHz quad core Intel Core i5 late 2013
Xbench: 152.36
Cinebench 10 Single core: 5235
Cinebench 10 Multi-core: 17592
iTunes encoding: 449.76 seconds (USB SuperDrive)
Movie encoding (iMovie): 146.49 seconds
Doom 3: 172.8 FPS
Call of Duty 4: 88.3FPS
Battery: N/A
Unigine Heaven 4.0, FPS: 9.7
Unigine Heaven 4.0, Score: 244
NovaBench, Score: 736
NovaBench, Graphics: 79

iMac 21.5-inch, 2.9GHz quad core Intel Core i5 late 2013
Xbench: 183.63
Cinebench 10 Single core: 5900
Cinebench 10 Multi-core: 19088
iTunes encoding: 451.8 seconds (USB SuperDrive)
Movie encoding (iMovie): 128.12 seconds
Doom 3: 222.0 FPS
Call of Duty 4: 88.6 FPS
Battery: N/A
Unigine Heaven 4.0, FPS: 19.1
Unigine Heaven 4.0, Score: 480
NovaBench, Score: 955
NovaBench, Graphics: 246

Intel claims its integrated Iris Pro graphics are a match for a discrete GPU, but our tests offered mixed results. When benchmarking the first-person shooter Doom 3 on the 2.7GHz 21.5-inch iMac with Iris Pro graphics, it achieved a frame rate of 172.8 frames per second (FPS).

On its sister machine, the 2.9GHz model with an Nvidia GeForce GT 750M GPU and 1GB of GDDR5 memory it ran at 222.0 FPS, so the integrated chipset didn't perform too shabbily.

It was a similar story in our Cinebench 3D rendering test. Using all four available cores, the more expensive of the two 21.5-inch iMacs scored 8.5% higher than its cheaper counterpart. Again, the integrated chipset did not embarrass it.

But in other tests, the lack of a discrete GPU held back the entry-level iMac. Using the Unigine Heaven 4.0 benchmarking tool, the 2.7GHz model managed 9.7 FPS, against the 2.9GHz version's 19.1 FPS. Their NovaBench graphics scores were 79 and 246 respectively.

There's no doubt that the new Intel integrated graphics are far more powerful than the HD Graphics 4000 built into the Ivy Bridge processors, and the lack of a discrete GPU won't hold back your web surfing, emailing and word processing. Even so, the more expensive 21.5-inch iMac is certainly worth the extra £150 (about US$250, AU$250) it costs, especially if you use a lot of graphics-intensive applications.

Comparing the entry-level late 2013 21.5-inch iMac with its mid-2010 counterpart shows just how far Apple's all-in-one computer has come over the last three years. The current iMac's Xbench score, which we use to measure CPU and storage performance, is over 31% higher. The Cinebench score when using multiple cores is almost 102% improved, and it encoded our five-minute test video into iPod format almost a minute quicker.

The newer iMac was over a minute slower when ripping our test CD using iTunes, but this is because we had to use an external USB SuperDrive, while the mid-2010 model had a built-in optical drive.

If you have a router that's 802.11ac-compatible, you can expect your wireless speeds to increase dramatically too. The new iMac retains the 2012 model's incredible new screen, which is fully laminated, eliminating a 2mm gap between the panel and its covering.

It also has an anti-reflective coating added using a new plasma deposition process, allowing it to be applied very thinly, for greatly reduced glare without affecting colour reproduction. The result? 75% less reflection, and deep, rich images. The iMacs' audio quality took a welcome upturn in 2012 too, and this again is retained here.

Verdict

The new iMac is gorgeous to behold. It's incredibly thin (around 5mm at the edges), and although there's a bulge in the centre where the computer components are housed, unless you're looking at it almost side-on, you hardly notice.

The late 2013 iMac retains the form factor used in the 2012 upgrade, but upgrades several key components. The processors are now Haswell chips, the graphics processor on the more expensive 21.5-inch model is an Nvidia 7 Series model and WiFi is now ac.

We liked

The iMac's performance has come on in leaps and bounds over the last few years. The late 2013 models certainly impress. The new Haswell processors are powerful and efficient, and although the off-the-shelf Core i5s lack a Hyper Threading feature, Turbo Boost gives them a welcome burst of speed when needed.

The Nvidia GeForce GT 750M GPU is definitely a step up from the previous generation's 6 Series Nvidia graphics, the move to 801.11ac gives improved wireless network speeds and if you opt for an SSD or Fusion Drive as a custom upgrade, the switch to PCIe connections makes them a little faster. There are some great custom options available on the Apple Online Store, especially for the more expensive of the two 21.5-inch models.

We disliked

The iMac's optical drive was sacrificed for the new slimline design. Not everyone will find this a fair exchange, but if you still need optical storage, it's easy enough to connect a USB DVD drive. Unlike the 27-inch iMacs, you can't upgrade the memory yourself after purchase. Indeed, iMacs are very difficult to upgrade at all.

Although we can live with the increase in the price, dropping the discrete graphics card from the entry-level iMac makes it better suited to a price drop than a rise. The more expensive smaller-screen iMac offers a faster processor and an Nvidia GeForce GT 750M with 1GB video memory for only £150 (about US$250, AU$250) more, which is surely better value for money.

Verdict

While the 2013 update is a welcome refresh, it's also nothing radical. Perhaps this is unsurprising coming less than a year after the radical redesign of late 2012. But it's nonetheless welcome, with a switch to Haswell processors and, for the more expensive 21.5-inch version, Nvidia 7 Series graphics.

We're not too happy about the discrete GPU vanishing from the entry-level, 2.7GHz model, though. With the 2.9GHz version costing only slightly more, we think it represents better value for money.