The 2012 Apple iMac is more than just a pretty case. It's been completely redesigned and re-engineered, with significant improvements in several key areas.
Take the screen. It's still an IPS display with edge-to-edge glass, a 1920 x 1080 pixel ratio and an ambient light sensor, but it's now fully laminated, losing a 2mm gap between the screen and its covering. This stops light reflecting off the LCD panel and the back of the glass screen.
According to Apple, it's never been attempted on a display this large before. An anti-reflective coating has been added to the glass using a new plasma deposition process, so that a very thin layer can be precisely applied.
The process, more commonly used for smaller surfaces such as camera lenses and fighter pilots' visors, cuts down on reflections without compromising the integrity of the colours. Overall, the display gives a 75% reflection reduction.
The new iMac uses third-generation Ivy Bridge quad-core Intel Core i5 processors across the 21.5-inch and 27-inch range. But if you buy the higher-specced model in each size, you can upgrade it to a quad-core Intel Core i7.
The model reviewed here enjoys this custom option, a 3.1GHz Core i7. The processor's Hyper-Threading feature means two threads can run on each of the four cores, giving eight virtual cores.
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It can also Turbo Boost, reallocating unused resources to temporarily boost the clock speed at times of high needs - temperature and power considerations permitting. This 3.1GHz Core i7 chip can reach up to 3.9GHz.
The graphics processor has also had an upgrade, to an Nvidia GeForce GT 650M graphics processor with 512MB of GDDR5 memory.
The new 21.5-inch iMacs don't have user-serviceable memory. If you want more than the 8GB of onboard RAM they're supplied with out of the box (up from 4GB in the previous generation), you have to order a custom build on the Apple online store, or take it to an Apple reseller.
The custom-configured model reviewed here has 16GB, which is the maximum for the smaller iMacs.
Audio has had a revamp too, with new, louder omnidirectional stereo speakers and dual microphones with beam forming technology to cut down on background noise.
This custom iMac also replaces the 1TB HDD with a 1TB Fusion Drive, which augments the traditional hard drive with 128GB of solid state storage for high-speed access to your most used files and applications.
The new iMac's four USB ports are all USB 3.0. It also has two Thunderbolt ports, which is one more than the previous generation. The FireWire 800 port is gone, but if you still use FireWire peripherals, you can get adaptors to fit them in your Thunderbolt ports.
The 2012 iMacs come with OS X 10.8: Mountain Lion and the latest iLife suite pre-installed, and are supplied with a wireless keyboard and Magic Mouse.
If you order online from the Apple Store, you can swap the keyboard for a full-sized USB model and/or replace the mouse with a Magic Trackpad if you wish.