What are all the differences between the final "2020" Aluminum iMac models? Which is best for me?

Please note that the "2020" Aluminum iMac models have been discontinued. However, this Q&A has been updated subsequently and remains quite useful for anyone buying or selling one of these systems on the used market.

There is a single line of "2020" Aluminum iMac models, all with 27" displays. More specifically, the stock "2020" 27-Inch iMac models are the iMac "Core i5" 3.1 27" (5K), "Core i5" 3.3 27" (5K), and "Core i7" 3.8 27" (5K).

Three configure-to-order configurations also were offered, which EveryMac.com crosslists separately because they have different processors and/or graphics processors as well as some different identifiers. These models are the iMac "Core i9" 3.6 27" (5K), "Core i7" 3.8 27" (5K; 5700/XT), and "Core i9" 3.6 27" (5K; 5700/XT).

These models look identical from the outside, but there are important internal differences that are not readily apparent, but that still merit a proper evaluation. It also is worthwhile to understand the similarities to determine which "2020" iMac is ideal for your needs.

Photo Credit: Apple, Inc. (2020 iMac)

External Similarities

All "2020" iMac models use an all aluminum case that tapers sharply to a 5 mm edge at the sides of the display. By default, this iMac line is not VESA compliant, but all could be configured with a VESA mount option instead of the aluminum stand at the initial time of purchase for an extra US$40.

All "2020" iMac models have a 27" 5120x2880 LED-backlit, 16:9 widescreen IPS DCI-P3, "Retina 5K" display with a brightness rating of 500 nits and True Tone technology, a first for the iMac line. True Tone evaluates the color temperature and ambient brightness of your surroundings and dynamically adjusts the display's white balance to match.

The 5120x2880 display looks like 2560x1440 at twice the density and has a fully laminated glass cover over the display and an anti-reflective coating. For an extra US$500, at the time of system purchase, Apple also offers this display with a "nano-texture glass" surface to more dramatically reduce glare, another first for the iMac line.

The "2020" iMac models also have a built-in 1080p "FaceTime HD" webcam mounted in the upper display bezel, a studio-quality three-mic array, and stereo speakers.

By default, each "2020" iMac model shipped with a compact aluminum Apple Magic Keyboard and the multi-touch "Magic Mouse 2". For an additional US$30, you originally couldupgrade from the default keyboard to the "Magic Keyboard with Numeric Keypad" and for an additional US$50, you also could upgrade from the Magic Mouse 2 to the "Magic Trackpad 2," which provides multi-touch and pressure-sensitive "Force Touch" capabilities.

Connectivity Similarities

Connectivity is identical for all of the "2020" iMac models.

All "2020" iMac systems have an SDXC-capable (UHS-II) SD card slot, four USB 3.0 (USB-A) ports, two Thunderbolt 3 (USB-C) ports, one Gigabit Ethernet port (10/100/1000Base-T), and one 3.5 mm headphone jack. 10-Gigabit Ethernet also was available at the initial time of syste, purchase as a US$100 upgrade.

The "2020" iMac series also supports 802.11ac Wi-Fi, which is backwards compatible with the slower 802.11a/b/g/n standards, as well as Bluetooth 5.0.

Using a Thunderbolt 3 port, all "2020" iMac models can simultaneously support the internal display at full native resolution and up to one 6016x3384 (6K) external display at 60 Hz with support for 1 billion colors; one 5120x2880 (5K) external display at 60 Hz with support for 1 billion colors; two 3840x2160 (4K UHD) external displays at 60 Hz with support for 1 billion colors; or two 4096x2304 (4K) external displays at 60 Hz with support for millions of colors.

Identification Differences

The "2020" 27-Inch iMac models share the A2115 model number with the earlier "2019" models of the same size.

The model number is sufficiently unique to upgrade the RAM, but not storage, so other identifiers are better for more precise identification.

In software, the Model Identifier is sufficiently unique for just about all purposes. Externally, the EMC number is best as it is is not shared by other models using the same case type, although it is inconveniently located on the underside of the stand.

These identifiers for the "2020" iMac models are as follows:

Tapered Edge iMac	Subfamily	Model ID	EMC No.
"Core i5" 3.1 27"	2020, 5K	iMac20,1	3442
"Core i5" 3.3 27"	2020, 5K	iMac20,1	3442
"Core i7" 3.8 27"	2020, 5K	iMac20,1	3442
"Core i9" 3.6 27"	2020, 5K	iMac20,1	3442
"Core i7" 3.8 27" (XT)	2020, 5K	iMac20,2	3442
"Core i9" 3.6 27" (XT)	2020, 5K	iMac20,2	3442

Additionally, EveryMac.com's Ultimate Mac Lookup feature also can uniquely identify each of the "2020" iMac models by their serial numbers.

Internal Differences

Internally, there are significant differences between the "2020" iMac models including processors, storage, and video processors as well as upgrade options for all three.

All "2020" iMac models use "10th Generation" Intel "Comet Lake" processors and have AMD Radeon Pro graphics with dedicated GDDR6 memory, but different models have different processors and graphics processors.

All "2020" iMac models have a small "pop off" door on the rear that make accessing the RAM quick and easy and all have four 2666 MHz PC4-21300 DDR4 SDRAM SO-DIMMs (260-pin) slots and can support a maximum of 128 GB of RAM.

Unfortunately, as first determined by site sponsor OWC, the SSD in these models, by default, is soldered onboard and cannot be upgraded. However, a subsequent OWC teardown was able to confirm earlier speculation that if the higher-end iMac "Core i7" 3.8 (5K, 2020) (MXWV2LL/A) was equipped with the 4 TB or 8 TB SSD option at the time of purchase (but not smaller SSDs), half of the storage is onboard and the other half is mounted on an expansion board. Accordingly, future storage upgrades could be possible for high-end custom configured models, just needlessly complicated. Accessing the storage effectively requires you to pry off the display and disassemble the computer.

"2020" iMac Comparison Chart

The major differences between the "2020" 27-Inch iMac models are summarized below:

	i5 3.1 (2020)	i5 3.3 (2020)	i7 3.8 (2020)
Std. Processor Speed:	3.1 GHz	3.3 GHz*	3.8 GHz*
Std. Processor Type:	Core i5	Core i5*	Core i7*
Std. Processor Cores:	6	6	8
Turbo Boost:	4.5 GHz	4.8 GHz*	5.0 GHz*
Processor Options:	No	Yes*	Yes*
Std. Storage:	256 GB	512 GB	512 GB
Storage Options:	None	1, 2 TB	1, 2, 4, 8 TB
SSD Connector:	No	No	No/Yes†
Std. RAM:	8 GB	8 GB	8 GB
Radeon Pro:	5300	5300	5500 XT♦
Video Memory:	4 GB	4 GB	8 GB♦
Video Options:	No	No	Yes♦
Apple Order No (US):	MXWT2LL/A	MXWU2LL/A	MXWV2LL/A
Apple Model ID:	iMac20,1	iMac20,1	iMac20,1♦
Original Price (US):	US$1799	US$1999	US$2299
Original Price (CA):	C$2399	C$2649	C$3079
Original Price (UK):	£1799	£1999	£2299
Original Price (AU):	A$2799	A$3099	A$3549

* By custom configuration, the iMac "Core i5" 3.3 27" (5K), and "Core i7" 3.8 27" (5K) could be configured with a 3.6 GHz 10-Core "Core i9" processor (I9-10910) for an extra US$500 or US$400, respectively. This processor has a 20 MB level 3 cache and Turbo Boost up to 5.0 GHz. EveryMac.com also has documented these custom configurations as its own model.

† If this model was equipped with the 4 TB or 8 TB SSD option at the time of purchase (but not smaller SSDs), the flash module is mounted on an expansion board with a connector to the logic board; future storage upgrades could be possible.

♦ At the time of system purchase, this model could be upgraded to an AMD Radeon Pro 5700 with 8 GB of GDDR6 memory for an extra US$300 or an AMD Radeon Pro 5700 XT with 16 GB of GDDR6 memory for an extra US$500. If the video processor was upgraded, the system uses the iMac20,2 identifier. EveryMac.com crosslists these models as their own systems, accordingly -- the iMac "Core i7" 3.8 27" (5K; 5700/XT) and "Core i9" 3.6 27" (5K; 5700/XT).

So, which one should I buy?

Although the value proposition has changed somewhat on the used market (they are definitely cheaper now), but at the initial time of release, none of the "2020" 27-Inch iMac models were inexpensive, and subsequently introduced "Colors" iMac models are well worth considering, as well.

However, EveryMac.com would suggest that if you are on a budget, the entry-level iMac "Core i5" 3.1 27" (5K) was a better choice than the smaller, older 21.5-Inch iMac models because these 27-Inch models have a newer, faster architecture and RAM that is easy to upgrade. It is unfortunate that the internal storage is soldered in place, but Thunderbolt 3 ports make external storage quick and easy.

The mid-range stock model -- the iMac "Core i5" 3.3 27" (5K) -- is barely faster than the entry-level model, but also doubles the storage for what was originally a US$200 price increase, so it was not a bad value, but it is a less impressive jump than the stock high-end model -- the iMac "Core i7" 3.8 27" (5K) -- which is much faster (37% in multicore tasks), but only originally cost 28% more (US$400) and doubles the storage.

The custom configured models with even faster processors and graphics -- the iMac "Core i9" 3.6 27" (5K), "Core i7" 3.8 27" (5K; 5700/XT), and "Core i9" 3.6 27" (5K; 5700/XT) -- initially increased the price significantly and mostly were best to be considered by those who did demanding tasks that were heavily dependent on performance, especially graphics performance. The "Core i9" processor upgrade alone originally added another 17% to the price for a 16% increase in performance, so it was not as worthwhile of an increase on a percentage basis, but for those who use their iMac to make money, these models could still be worthwhile. Time is money, after all.

For the majority of users, though, the best value likely originally was either the entry-level iMac "Core i5" 3.1 27" (5K) or the standard high-end iMac "Core i7" 3.8 27" (5K). On the used market, prices are lower, but these general guidelines still remain worthwhile when comparing these models to each other.

Please also see EveryMac.com's Ultimate Mac Comparison feature to dynamically compare any iMac model to any other Mac.

In the US, site sponsor Adorama sells new iMac models with free shipping. Other World Computing and JemJem sell used and refurb iMac models at bargain prices with free shipping, as well. Finally, if you need to sell an iMac, A+ BBB-rated Cash for Your Mac will buy your older iMac with an instant quote and prompt payment.

In the UK, site sponsor Hoxton Macs sells used iMac models with a one-year warranty and free next day delivery throughout the UK. Delivery across Europe also is available starting at just £9.99 for two-day delivery to France and Germany.

In Australia, site sponsor Mac City likewise has a variety of used iMac models sold at low prices and available with a free warranty and fast shipping across Australia.