The iMac "Core i9" 3.6 27-Inch Aluminum (Retina 5K, 2020/Comet Lake) features a 14-nm "Comet Lake" 3.6 GHz Intel "Core i9" processor (I9-10910) with ten independent processor "cores" on a single chip, a 20 MB shared level 3 cache, a T2 Security Chip, 8 GB of easy to upgrade 2666 MHz DDR4 SDRAM, a 512 GB onboard default SSD, and an Radeon Pro 5300 graphics processor with 4 GB of dedicated GDDR6 video memory or a Radeon Pro 5500 XT graphics processor with 8 GB of dedicated GDDR6 video memory. It also has a built-in 1080p "FaceTime HD" webcam, a studio-quality three-mic array, and stereo speakers.

This model has a 27" 5120x2880 LED-backlit 16:9 widescreen IPS DCI-P3 "Retina 5K" display with True Tone technology. The rear of the case is aluminum and is thicker in the middle and tapers to a razor thin 5 mm at the edges.

Connectivity includes four USB 3.0 ports, dual Thunderbolt 3 (USB-C) ports, Gigabit Ethernet, 802.11ac Wi-Fi, and Bluetooth 5.0.

Compared to its predecessor, this model looks nearly identical, but has a display with "True Tone" technology (and a new option of a "nano-texture" surface for an extra US$500), a better webcam, speakers, and microphone as well as a more advanced processor, architecture, and graphics processor.