The exterior of the iMac looks identical to the 2014 model, with the same aluminum and glass body. It measures 17.7 by 20.8 by 6.9 inches (HWD) and weighs 12.5 pounds.The 21.5-inch Retina display is the real star here. With a resolution of 4,096 by 2,304, the In-Plane Switching (IPS) screen has 4.5 times the resolution of a 1080p HD display. That means you can have four 1080p HD video windows playing at native resolution simultaneously, or you can fill the screen with a 4K video from your iPhone 6s or other sources.The 21.5-inch screen has 9.4 million pixels compared with the 14.7 million (5,210-by-2,880 resolution) on the latest Apple iMac 27-inch with 5K Retina display.With a relatively small footprint users are apt to tuck their 4K iMac onto an equally small workspace or in a nook, leaving little room for rear panel access.Apple chose to overhaul its peripherals lineup this year with the Magic Keyboard and Magic Trackpad 2 now sporting low-profile wedge shapes reminiscent of beautifully crafted doorstops.Each of Apple’s new input devices look more at home next to iMac than their prior iterations thanks in no small part to non-replaceable rechargeable batteries.
The display of Apple’s new 21.5 inch 4K iMac is its real star attraction and the piece of the machines hardware that comes with the most impressive specs in our book. While Apple dropped the ball a bit on internal hardware specs in this machine, they really invested in some stunning visual capacity which sincerely impresses. The 4K iMac is capable of handling a plethora of different resolutions depending on your needs and desires, and the internal OS X El Captitan operating system scales accordingly to handle all of them wonderfully. Since El Capitan was built with UHD compatibility baked right into it from the ground up, there should be no scaling problems to speak of with the iMac’s native software components or other Apple accessory software.At a maximum native resolution of 4096 x 2304 pixels, the new iMac takes 4K to very new and highly uncommon levels of True 4K resolution which aren’t even found in the few other PC monitors on the market which do feature above-3840 X 2160 pixel resolution. The more usual True 4K spec is 4096 x 2160 and this iMac beats even that for a total of 9.4 million pixels on its screen, at a very robust pixel density of 217 ppi.with Apple’s inclusion of the DCI-03 color space commonly used for digital cinema in movie theaters and other professional applications, the 4K iMac offers a much broader range of exquisite color shades, particularly for reds and greens, affecting the range and richness of tertiary colors like yellow, orange, magenta and cyan. In other words, the 4K iMac includes all the colors that make up the simpler sRGB spectrum and then takes them a whole lot further into pro territory. Apple is also using red-green phosphor LEDs to expand color gamut in its LCD screen.
In a single row on the back of the chassis is a collection of ports and connections, including four USB 3.0 ports, two Thunderbolt/mini-DisplayPort connections, an SD card slot, Ethernet jack and a headphone plug. The only real difference this year is that the Thunderbolt ports have been upgraded from the original Thunderbolt spec to the newer Thunderbolt 2. Missing is USB-C, the small, reversible plug found in the 12-inch MacBook and a handful of Windows PCs.
Equipped with an Intel Core i5-5675R processor with Intel Iris Pro 6200 graphics, the system performed quite well on our multimedia tests, making it well-suited for video editing and production tasks.The iMac is also an excellent photo-editing tool.This new iMac is a multimedia powerhouse.3D performance is good for a system with integrated graphics.The real benefit, year over year, of having the latest Intel processors, is improved power-efficiency and better battery life, which are more important for laptops and hybrids than for desktops.In hands-on use, the new iMac felt very zippy, even when playing back 4K video files, manipulating large photo files, or jumping between multiple browsers and multimedia apps. while you can play back and even edit 4K video on the new iMac, a gaming machine this is not.
The base storage configuration of the 4K iMac is a 1TB, 5400rpm hard drive.Apple has packed an impressive amount of technology into this iMac, but it seems almost unforgivable that a Retina iMac could be saddled with a slow spinning hard drive. You can pay a bit extra to equip a Fusion Drive, which combines the capacity of a spinning disc with a small amount of speedy flash storage.If you regularly use large media files, you’ll want to opt for the larger Fusion Drive or pure flash storage, but the cheaper configuration is a great option for users who don’t stress out their Macs quite as much.the 4K iMac benefits from the same storage speed boost that we saw earlier this year on the MacBook Pro.These models can take advantage of upgraded storage controllers and 4 lanes of PCI to achieve flash-storage transfer speeds up to 2.5 times those of previous models. All the more reason to jump off the spinning-hard-drive train before it crashes and switch to a Fusion Drive or pure flash storage.
The 4K iMac’s main draw is its gorgeous Retina display. For desktop users interested in having the best display around, the 21.5-inch 4k iMac is an easy recommendation with one caveat: it needs the HDD upgrade. The 4K display might be something of a luxury for business users who simply want to run Microsoft Office, but its impressive image quality and the strong performance of the Broadwell processor mean that the 21.5-inch iMac with Retina 4K Display will be an attractive option for users who need a fast and versatile desktop computer.