iMac 27-inch Retina 5K (2017): Refurbished, Specs & Repairs

About This Model

The iMac 27-inch Retina 5K (2017) was released in June 2017 and sold until the 2019 model replaced it. It brought faster processors, much stronger graphics and a 500-nit display compared with the 2015 model.

Complete Mac Solutions supplies refurbished Apple Macs in Bristol for home users, students and businesses. We also offer iMac repairs and can help you compare the cost of repairing or upgrading an older iMac with a suitable replacement.

Which iMac does this cover?

This guide covers the iMac (Retina 5K, 27-inch, 2017), with the model identifier iMac18,3. It looks identical to the 27-inch iMacs from 2014 to 2020, so check the full model name rather than relying on the case.

Choose About This Mac from the Apple menu to check the model. The 2017 model has a quad-core Intel Core i5 at 3.4GHz, 3.5GHz or 3.8GHz, or an optional 4.2GHz Core i7, with Radeon Pro 570, 575 or 580 graphics. It has two Thunderbolt 3 ports, while the 2015 model has Thunderbolt 2.

Specifications at a glance

Display	27-inch Retina 5K display, 5120 × 2880 resolution, 500 nits, P3 wide colour
Processor options	3.4GHz, 3.5GHz or 3.8GHz quad-core Intel Core i5; optional 4.2GHz quad-core Core i7
Memory	8GB 2400MHz DDR4 as standard; four slots; up to 64GB on most models
Original storage options	1TB, 2TB or 3TB Fusion Drive, or 256GB up to 2TB SSD
Graphics	Radeon Pro 570 (4GB), 575 (4GB) or 580 (8GB)
Connections	Two Thunderbolt 3 (USB-C) ports, four USB-A ports, Gigabit Ethernet, SDXC card slot and headphone socket
Wireless	802.11ac Wi-Fi and Bluetooth 4.2
Size and weight	51.6cm high, 65cm wide, 20.3cm stand depth; approximately 9.4kg

Ask us to confirm the exact configuration of any refurbished machine available. Storage may have been replaced or upgraded from the original factory specification.

What is it useful for?

Our recommendation is to assess this model for photo editing, design, music production, office work and compatible creative software. The large 5K screen is excellent for detailed work and for having several windows open side by side.

It is not equivalent to a current Mac for demanding work. Recent professional software increasingly needs a newer macOS. An iMac with an SSD feels far quicker than one with the original Fusion Drive.

A Mac for Bristol students

For Bristol students on design, photography or music courses, a 2017 27-inch iMac can be an affordable way to get a big, sharp, colour-accurate screen for a desk at home.

Check university requirements before choosing an older Mac, as many current applications and examination tools need a newer macOS. If you need a main computer for several years of study, compare it with a newer model, and ask about our student deals.

Macs for businesses

Complete Mac Solutions supplies Macs for businesses as well as individuals. Tell us which applications, peripherals and working arrangements your team uses so we can help you choose a suitable machine.

A 2017 27-inch iMac can suit design studios, estate agents and offices that work with large documents and images, using compatible software. Check application support and your organisation’s security requirements before using it as a staff computer.

macOS compatibility

Apple lists macOS Ventura as the newest officially compatible operating system for this model. That is an important buying limitation: current applications may require a newer macOS release, and Ventura no longer receives security updates.

Check the developer’s requirements for your essential applications before purchasing. Tell us what you need to run so we can help you compare suitable alternatives.

Memory and storage upgrades

Memory is easy to upgrade through the access door on the back, with four slots. The 3.5GHz and 3.8GHz models support up to 64GB, and the 3.4GHz model up to 32GB, which makes this a good iMac for heavy multitasking.

Replacing the Fusion Drive with an SSD is the most worthwhile upgrade, but it means removing the bonded glass display, so it is a job for a technician.

Upgrades can make a big difference to everyday speed, but they will not extend official macOS support. Ask us about the exact machine before deciding whether an upgrade is worthwhile.

Known concern: Fusion Drives

Most of these iMacs were supplied with a Fusion Drive, which combines a small SSD with a traditional hard drive. After years of use the hard drive part often becomes slow or starts to fail, which shows as a spinning wheel, long startup times and freezing.

Back up important files first, and ask about data recovery if the drive has already failed.

Other repair symptoms to check

Display faults

Check the screen for lines, dark patches, flickering or a dim backlight, and inspect the glass for cracks. Display repairs involve the bonded glass panel, so get an assessment before deciding.

Startup and power problems

Failure to start, random shutdowns or a machine that powers on without a picture can have several causes, including the internal power supply. Tell us what happens when you press the power button.

Heat, fan noise and Wi-Fi

A loud fan, heat-related slowdowns or unreliable Wi-Fi or Bluetooth deserve assessment. Describe when the problem started and whether it happens during particular tasks.

Complete Mac Solutions can discuss iMac repairs in Bristol and help you weigh the likely cost against the condition, usefulness and replacement value of the machine.

Buying a refurbished iMac 27-inch Retina 5K (2017)

Confirm the processor, graphics, memory, storage type and capacity, the installed version of macOS and the condition of the display. Most importantly, check that your essential software supports its operating system.

Complete Mac Solutions carries a large stock of refurbished Macs and has an extensive supplier network to help source suitable configurations. Many of our Macs come fully boxed, with all accessories and in fantastic condition. Packaging, accessories and condition vary between machines, so ask us to confirm what comes with the one you choose.

Explore our Apple Macs for sale or speak to us about a desktop for home, study or business. If you already own this model, we can help you consider whether repair, an upgrade or replacement offers the best value.

References and further reading

• Apple: iMac (Retina 5K, 27-inch, 2017) technical specifications

Compare the iMac 27-inch Retina 5K (2017) with similar models

The 2019 model adds six-core and eight-core processors on the same design. The 2015 model is often cheaper, and the iMac Pro offers workstation-class power in a space grey case.

• iMac 27-inch Retina 5K (2019)
• iMac 27-inch Retina 5K (2015)
• iMac Pro (2017)
• iMac 21.5-inch Retina 4K (2017)

Buy or repair an iMac 27-inch Retina 5K (2017)

Looking for a big-screen iMac with easy memory upgrades? Ask about our current iMac stock, or let us diagnose and quote for a repair or SSD upgrade on the one you already own.