Graphical Glitches Plaguing Some 2020 iMac Owners With Radeon Pro 5700 XT GPU

Apple in August refreshed the 2020 iMac lineup with a new 27-inch model that's equipped with 10th-generation Intel processors, more RAM, more SSD settings, and faster AMD GPUs.

imac 27 inch
Unfortunately, some new Mac owners have been running into problems with their machines and have been reporting ongoing glitching with the graphics. There's a 57-page thread on the MacRumors forums filled with complaints dating back to August, suggesting this is a problem that's been impacting ‌iMac‌ owners since the new Macs came out.


Based on a poll, a good number of ‌iMac‌ owners who have the higher-end 5700XT GPU are seeing a white horizontal line flicker across the display on occasion, but the problem does not seem to impact all users. MacRumors reader torifile describes the issue:

I got my 2020 iMac Thursday night. It's as fast as expected and gorgeous. Last night I thought I saw, out of the corner of my eye, a horizontal white line flash mid-way up the screen. It was really fleeting and I thought I was just seeing things. This morning, I saw the same thing. The computer isn't running hot or anything. iStat Menus has all the cores untaxed. I recall having this same problem with my MBP 13" (2019) with an earlier version of macOS (I can't remember if it was a late Mojave build or an early Catalina) and it was cleared up with a software update.

The white line described by those affected appears to flash across the screen at random intervals throughout the day, and there are some other seemingly related graphical issues that ‌iMac‌ owners have run into. Some users have reported being able to remedy the problem by choosing a scaled resolution other than the default, but that's not an ideal longterm solution.

It's not clear if the issue that ‌iMac‌ owners are experiencing is hardware or software based, but Apple has not yet implemented a fix for the problem.

Related Roundup: iMac
Buyer's Guide: iMac (Caution)
Related Forum: iMac

Popular Stories

iOS 26

iOS 26.2 Coming Soon With These 8 New Features on Your iPhone

Thursday December 11, 2025 8:49 am PST by
Apple seeded the second iOS 26.2 Release Candidate to developers earlier this week, meaning the update will be released to the general public very soon. Apple confirmed iOS 26.2 would be released in December, but it did not provide a specific date. We expect the update to be released by early next week. iOS 26.2 includes a handful of new features and changes on the iPhone, such as a new...
iOS 26

iOS 26.4 and iOS 27 Features Revealed in New Leak

Friday December 12, 2025 10:56 am PST by
Macworld's Filipe Espósito today revealed a handful of features that Apple is allegedly planning for iOS 26.4, iOS 27, and even iOS 28. The report said the features are referenced within the code for a leaked internal build of iOS 26 that is not meant to be seen by the public. However, it appears that Espósito and/or his sources managed to gain access to it, providing us with a sneak peek...
AirPods Pro Firmware Feature

Apple Releases New Firmware for AirPods Pro 2 and AirPods Pro 3

Thursday December 11, 2025 11:28 am PST by
Apple today released new firmware designed for the AirPods Pro 3 and the prior-generation AirPods Pro 2. The AirPods Pro 3 firmware is 8B30, up from 8B25, while the AirPods Pro 2 firmware is 8B28, up from 8B21. There's no word on what's include in the updated firmware, but the AirPods Pro 2 and AirPods Pro 3 are getting expanded support for Live Translation in the European Union in iOS...
iOS 26

Apple Releases iOS 26.2 With Alarms for Reminders, Lock Screen Changes, Enhanced Safety Alerts and More

Friday December 12, 2025 10:10 am PST by
Apple today released iOS 26.2, the second major update to the iOS 26 operating system that came out in September, iOS 26.2 comes a little over a month after iOS 26.1 launched. ‌iOS 26‌.2 is compatible with the ‌iPhone‌ 11 series and later, as well as the second-generation ‌iPhone‌ SE. The new software can be downloaded on eligible iPhones over-the-air by going to Settings >...
Google maps feaure

Google Maps Quietly Added This Long-Overdue Feature for Drivers

Wednesday December 10, 2025 2:52 am PST by
Google Maps on iOS quietly gained a new feature recently that automatically recognizes where you've parked your vehicle and saves the location for you. Announced on LinkedIn by Rio Akasaka, Google Maps' senior product manager, the new feature auto-detects your parked location even if you don't use the parking pin function, saves it for up to 48 hours, and then automatically removes it once...
AirTag 2 Mock Feature

Apple AirTag 2: Four New Features Found in iOS 26 Code

Thursday December 11, 2025 10:31 am PST by
The AirTag 2 will include a handful of new features that will improve tracking capabilities, according to a new report from Macworld. The site says that it was able to access an internal build of iOS 26, which includes references to multiple unreleased products. Here's what's supposedly coming: An improved pairing process, though no details were provided. AirTag pairing is already...
macOS Tahoe 26 Thumb

Apple Releases macOS Tahoe 26.2 With Edge Light

Friday December 12, 2025 10:08 am PST by
Apple today released macOS Tahoe 26.2, the second major update to the macOS Tahoe operating system that came out in September. macOS Tahoe 26.2 comes five weeks after Apple released macOS Tahoe 26.1. Mac users can download the macOS Tahoe update by using the Software Update section of System Settings. macOS Tahoe 26.2 includes Edge Light, a feature that illuminates your face with soft...
iOS 26

15 New Things Your iPhone Can Do in iOS 26.2

Friday December 5, 2025 9:40 am PST by
Apple is about to release iOS 26.2, the second major point update for iPhones since iOS 26 was rolled out in September, and there are at least 15 notable changes and improvements worth checking out. We've rounded them up below. Apple is expected to roll out iOS 26.2 to compatible devices sometime between December 8 and December 16. When the update drops, you can check Apple's servers for the ...

Top Rated Comments

AAPLGeek Avatar
68 months ago
Apple has already addressed this by updating the product page



Attachment Image
Score: 16 Votes (Like | Disagree)
b656 Avatar
68 months ago
if only nVidia and Apple were friends...
Score: 15 Votes (Like | Disagree)
dinobear Avatar
68 months ago
How is this not apple's fault? They decided on the hardware, wrote the software, and built the machine. They are responsible for what is delivered as a final product.

If they can't figure out how to make existing architectures work in a form factor thats been around for 10 years, goodluck on thier new endevors ?

I love apple dont get me wrong, but they''re not perfect and they should be held accountable for thier mistakes.
Score: 12 Votes (Like | Disagree)
Grohowiak Avatar
68 months ago
I wish MR would write a big piece on the 16" GPU issues.
Unless there was one but I don't recall.
Ultimately AMD drivers / hardware sucks lately.
Score: 11 Votes (Like | Disagree)
teagls Avatar
68 months ago

Good question, apparently it’s Apple? Based on what they say on their site.

But surely AMD give them a tonne of base code to work from.
It's Apple's fault. At the end of the day Apple is solely responsible for the development and release of it's drivers. AMD provides assistance, but Apple controls the whole thing.
Score: 9 Votes (Like | Disagree)
AZREOSpecialist Avatar
68 months ago
Thank you Macrumors for writing about this!
Score: 7 Votes (Like | Disagree)