Following on from the new cheaper iMac unveiled on 18 June, Apple has gone to the other end of the spectrum to release a 27in Retina 5K iMac. The impressive new iMac was shown off during Apple's 16 October event alongside the iPad Air 2, iPad mini 3 and a new Mac mini. Here, we bring you everything you need to know, including the new iMac's specs, features, UK price and release date.

To discover our first impressions of the Retina 5K iMac, take a look at our hands-on Retina iMac review

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27in Retina 5K iMac release date: When can I buy the Retina iMac?

Surprise! The 27in Retina 5K iMac is available to buy now. Apple opened up orders for the new all-in-one desktop computer immediately after its 16 October event.

You can buy the Retina iMac, as well as the rest of the iMac line-up which remains unchanged, from Apple's online store.

At present, the Apple Store is suggesting that the new iMac will begin shipping within 3-5 days, but we expect that wait time to increase dramatically if demand for the new iMac is high.

Retina iMac release date

27in Retina 5K iMac price: How much does the Retina iMac cost?

The 27in Retina 5K iMac starts at £1,999 for the base model, which has a 3.5GHz quad-core Intel Core i5 processor, 8GB RAM, a 1TB Fusion Drive, and AMD Radeon R9 M290X with 2GB video memory.

If you're after the top spec built-to-order Retina 5K iMac, you'll be looking at a price tag of up to £3,515, which gets you a 4GHz quad-core i7 processor, 32GB RAM, 1TB Flash storage (a 3TB Fusion Drive is available too and is a bit cheaper) and even better graphics.

The price of the rest of the Macs in the iMac line-up remain unchanged.

27in Retina 5K iMac: Design

The design of the new Retina iMac is the same as the other iMacs in the line-up, with a super-thin 5mm edge and seamless design despite the brand new display.

27in Retina 5K iMac: Display

The lack of design changes means we can move straight on to the display, which is the real talking point of this incredible new iMac. The 27in Retina display contains a total of 14.7 million pixels (5120 x 2880 resolution). It's made from 23 layers, despite being just 1.4mm thick.

In addition to the impressive new resolution, the Retina display also means blacker blacks and more vibrant colours, according to Apple.

Plus, it uses "highly efficient LEDs" to mean that, even though there are so many more pixels to power, (four times as many, to be presise) it actually uses 30 per cent less power according to Apple.

27in Retina 5K iMac: Specs

Taking a closer look at the new iMac's specs, you'll find a 3.5GHz quad-core Intel Core i5 processor inside with the option to upgrade to 4.0Ghz. It's not Intel's next generation Broadwell processor, which we'd originally thought Apple might wait for before launching the new iMac.

However, new Skylack processors are expected to land next year so perhaps Apple will skip Broadwell and go straight for the following generation when it updates the full range of iMacs next year.

Apple offers a 1TB Fusion Drive as standard in the Retina iMac, which means you get fast Flash storage combined with the high capacities of a traditional hard disk. Build-to-order options are available, too.

When it comes to RAM, as mentioned above, you'll get 8GB 1600MHz DDR3 SDRAM as standard. 

The graphics card is AMD R9 290x, with the option of upgrading to AMD R9 295x at checkout, rather than the Nvidia graphics cards found in Apple's other iMacs.

Ports include an SDXC card slot, four USB 3.0 slots, two Thunderbolt ports, a Gigabit Ethernet Jack and the faster Thunderbolt 2, which sets it apart from the other iMacs in the range.

Want more information on the new Macs? Here's the Macworld team discussing the hits and misses of Apple's 16 October launch event, including the Retina iMac:

And see page 2 for everything we wrote about the Retina iMac rumours ahead of its official launch.