In 2014 Apple unveiled a new cheaper iMac in June, and then went to the other end of the spectrum and released a 27in Retina 5K iMac in October, alongside the iPad Air 2, iPad mini 3 and a new Mac mini. However, notably absent from 2014’s upgrade cycle was the rest of the iMac range, with the four original iMacs remaining untouched since they were updated on 24 September 2013.

Here, we bring you everything you need to know about when Apple will upgrade the rest of the iMac range, including the new iMac's specs, features, UK price and release date.

To discover what we think about the Retina 5K iMac, take a look at our Retina iMac review. If you are in the market for a new Mac, read our iMac or Mac mini - Mac desktops compared and Best Mac to buy: Mac Buying Guide.

How long has it been since Apple updated the iMac?

If you ignore the £899 iMac and the Retina iMac, which were both introduced in 2014, the last time the iMac saw a proper update was in September 2013 when Apple added the Haswell processor, new graphics, next generation Wi-Fi and faster PCIe flash storage options. Read our review of the 2013 iMacs. You can read all our iMac reviews here.

When will the new iMacs launch?

We think that a new iMac launch will come this summer, along with an update to the 15in MacBook Pro. The new Macs may appear in conjunction with Apple’s WWDC, which being a pro focused event would be a good location for the news. Read about what else we expect to see at Apple’s WWDC in June here.

Why hasn’t Apple updated the iMac?

We're pretty confident that the reason why Apple hasn’t updated the rest of the iMac range in such a long time is that it was waiting for Intel to release its the Broadwell chips - which were delayed (read more about this below).

New iMac specs: Price

Another important question is how much will the new iMacs cost if, and when, they do launch?

The current line up is priced as follows:

  • 21.5in, 1.4GHz dual-core i5, £899
  • 21.5in, 2.7GHz quad-core i5, £1,049
  • 21.5in, 2.9GHz quad-core i5, £1,049
  • 27in, 3.2 quad-core i5, £1,449
  • 27in, 3.4 quad-core i5, £1,599
  • 27in, Retina 5K display, 3.5 quad-core i5, £1,999

We expect that Apple won’t change the prices when the new models launch, although it is possible that the second generation of the Retina display iMac may come down in price, or that the other 27in iMacs may gain Retina displays and go up in price, more on that below.

Will the other Macs get a Retina display?

There is already a 27in iMac with Retina display, so it is possible that the other 27in models could see a screen update. It is likely that Apple will eventually role out the new display to these 27in models, although it may be biding time while the price comes down.

As for the 21in iMacs, we don’t think these will get a Retina display yet, predominantly because adding a Retina display would make these models significantly more expensive, and we think Apple will maintain their positioning as consumer Macs.

New iMac specs: processor

The new £899 iMac gained a 1.4GHz processor, the Retina iMac runs a xxx processor. Why didn’t the other iMacs get updated?

Everyone has been waiting for Intel’s Broadwell processor to arrive in the iMac, but those new Intel processors have been delayed to such an extent that it is thought that Apple may even be waiting for their successor – Skylark – to launch.

Intel’s next generation of processors, Broadwell, have faced major delays. Anyone awaiting a new iMac or new 15in Retina MacBook Pro should note that while there are now various Broadwell chips beginning to ship, for example the Core-M in the MacBook and the new i5 chips in the MacBook Air models, and the 13in MacBook Pro, the Quad-Core chips destined for the 27in iMac and the MacBook Pro have not yet shipped. Recent reports suggest that these will ship in the second quarter of this year – so hopefully before June.

Broadwell uses the 14nm manufacturing process and is said to consume 30% less power than its predecessor Haswell. That should be good news for battery life on the portable Macs, but also for those Macs with especially power hungry screens.

However, the successor to Broadwell, Skylark is on the horizon, and due to launch in 2015. Skylark will also use the 14nm manufacturing process, but it will bring even greater CPU and GPU performance, along with reduced power consumption. Features of Skylark will include PCI Express 4.0 and Thunderbolt 3.0, which are likely to appear in the Macs that feature those chips.

After Skylark the next round of processors will be Cannonlake, using the 10nm process but don’t expect to see them before 2017.

New iMac specs: storage

We really hope that Apple brings flash storage to the new range of iMacs in the form of a Fusion Drive, like the one added as standard to the Retina 5K iMac.

The current iMac range is crippled somewhat by the slower hard drives that Apple uses. While a hard drive has the benefit of offering more storage – in the case of these iMacs 1TB – it is a lot slower than the flash drives used in all of Apple’s laptops. To the extent that Mac laptops with similar processors will perform better than the equivalent iMac due to the faster SSD drive.

Apple offers a Fusion Drive currently as a £200 build to order option, we think it should be offered as standard in all Apple’s desktops. Alternatively Apple could start to offer flash drives as standard.

New iMac specs: Ports & USB Type-C

Of all the features on the new MacBook, USB Type-C has probably got the most attention - due to the fact that it’s the only port on the MacBook (read why we think the new MacBook doesn’t deserve all the criticism it’s getting).

When that Mac arrived with the single USB Type-C port there was some concern that it might spell the end for Thunberbolt. Given that Apple has strongly promoted this technology, which it describes as “revolutionary I/O technology that supports high-resolution displays and high-performance data devices through a single, compact port,” the company is very unlikely to be planning to drop it, plus as you can see above, Thunderbolt 3.0 is on its way.

The current line up of iMacs features Thunderbolt 1 (with the exception of the Retina iMac which has Thunderbolt 2). Thunderbolt 1 offers 10Gbp/s. Because they weren’t updated in 2014 these iMacs didn’t gain Thunderbolt 2, which offers 20Gbp/s. When it arrives Thunderbolt 3 will offer 40Gbp/s and be able to drive two external 4K displays (or a single external 5K display).

The USB Type-C port is compatible with USB 3.1 and therefore offers 10Gbp/s (double that of USB 3), but it also allows for charging, as it is able to deliver power at up to 100 watts at 20 volts. You are able to charge the MacBook via this port.

However, as yet USB-C only features on the new MacBook. Will it make its way onto the new iMacs? It seems likely that it will, but simply as a replacement for USB 3.0, we defiantly don’t expect it to replace Thunderbolt.

The current iMac line up offers the following ports and standards:

  • Headphone
  • SDXC card slot
  • Four USB 3 prots
  • Two Thunderbolt ports
  • Ethernet
  • Kensington lock slot  
  • 802.11ac WiFi
  • Bluetooth 4.0

New iMac specs: Graphics card

The current line up of iMacs features the Intel HD Graphics 5000 at the entry-level and the next model up offers Intel Iris Pro Graphics. You can expect to see updates to these cards – the new MacBook Pro 13in offers Intel Iris Graphics 6100, for example, so we’d expect this to appear in the iMacs too.

The higher-end iMacs feature NVIDIA GeForce graphics – the 21.5in iMac offers a GT 750M, the entry-level 27in has a GT 755M and the top of the range (excluding the Retina model) offers a GT 775M. The GeForce 700 series have been around for some time now, first introduced back in May 2013, so they could be described as a bit long in the tooth by now. The GeForce 800 series was introduced in March 2014, so even those graphics cards are now a year old. If Apple is going to stick with NVIDIA then it looks like the GT 900 (introduced in September 2014) might fit the bill. There’s a new GT 1000 series on the horizon, but it’s not expected until 2016.

The iMac with Retina display runs an AMD Radeon R9 M290X processor, so it is feasible that Apple might switch from NVIDIA to AMD, as they have in the past. The company may even move to integrated graphics cards, which are part of the motherboard, but if Apple does this it is likely to upset a lot of pro users.

New iMac specs: Design  

Could the design of the new iMacs change in the next generation? The slim unibody of the current style of iMac was introduced in November 2012, prior to that the design hadn’t really changed since 2009 when the Aluminium unibody design in 21.5in and 27in launched. Previous to that the Aluminium iMac launched in 2007 and came in 20in and 24in versions, and back in 2006 Apple launched the Intel iMac with it’s plastic finish, similar in design to the iMac G5 that launched in 2004. Two years prior to that was the lampstand-like iMac G4 in 2002, and in 1998 the original iMac launched.

That’s a change of design every two or three years, so some might think a new look iMac is due. However, we like the look of the current iMac and can’t think of any way it could change for the better, looking back at the generations of iMacs that preceded it, it does look like evolution to this point, we can’t imagine what can follow. Sure it can get thinner, but the weight and dimensions don’t really matter for a desktop machine.

Features some people would like to see probably include an extendable base to the iMac so that you can position it differently – currently it isn’t possible to raise up the iMac for a more ergonomic position. Aside from that people would probably like to see a Retina display come to the rest of the range.

Read our: 2014 iMac with Fusion Drive review and 2014 budget iMac review as well as our iMac Retina review and the review of the 2013 iMacs.