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

apple store down feature

Here's Why the Apple Store is Going Down

Thursday November 27, 2025 1:01 pm PST by
Apple's online store is going down for a few hours on a rolling country-by-country basis right now, but do not get your hopes up for new products. Apple takes its online store down for a few hours ahead of Black Friday every year to tease/prepare for its annual gift card offer with the purchase of select products. The store already went down and came back online in Australia and New Zealand, ...
Apple Foldable Thumb

Foldable iPhone to Debut These Three Breakthrough Features

Tuesday November 25, 2025 7:09 am PST by
Apple's first foldable iPhone is expected to launch alongside the iPhone 18 Pro models in fall 2026, and it's shaping up to include three standout features that could set it apart from the competition. The book-style foldable will reportedly feature an industry-first 24-megapixel under-display camera built into the inner display, according to a recent JP Morgan equity research report. That...
iPhone Pocket Short

iPhone Pocket is Now Completely Sold Out Worldwide

Tuesday November 25, 2025 7:16 am PST by
Apple recently teamed up with Japanese fashion brand ISSEY MIYAKE to create the iPhone Pocket, a limited-edition knitted accessory designed to carry an iPhone. However, it is now completely sold out in all countries where it was released. iPhone Pocket became available to order on Apple's online store starting Friday, November 14, in the United States, France, China, Italy, Japan, Singapore, ...
streaming black friday 2025

Black Friday Streaming Deals Include Big Savings on Disney+, Hulu, Apple TV, and More

Monday November 24, 2025 8:03 am PST by
We've been focusing on deals on physical products over the past few weeks, but Black Friday is also a great time of year to purchase a streaming membership. Some of the biggest services have great discounts for new and select returning members this week, including Disney+, Hulu, Paramount+, Peacock, and more. Note: MacRumors is an affiliate partner with some of these vendors. When you click a...
streaming black friday 2025

Best Black Friday Streaming Deals - Save Big on Apple TV, Disney+, Hulu, and More

Thursday November 27, 2025 1:14 pm PST by
We've been focusing on deals on physical products over the past few weeks, but Black Friday is also a great time of year to purchase a streaming membership. Some of the biggest services have great discounts for new and select returning members this week, including Apple TV, Disney+, Hulu, Paramount+, Peacock, and more. Note: MacRumors is an affiliate partner with some of these vendors. When...
General Black Friday Deals 25 Red Green

The 30+ Best Black Friday Apple Deals on AirPods, iPads, MacBooks, and More

Thursday November 27, 2025 6:46 am PST by
Black Friday is here, and as always this is the best time of the year to shop for great deals, including popular Apple products like AirPods, iPad, Apple Watch, and more. In this article, the majority of the discounts will be found on Amazon. Note: MacRumors is an affiliate partner with some of these vendors. When you click a link and make a purchase, we may receive a small payment, which...
General Apps Messages Redux

Singapore Orders Changes to iMessage by December

Tuesday November 25, 2025 6:39 am PST by
Singapore has ordered Apple to block or filter messages on iMessage that impersonate government agencies, requiring the company to implement new anti-spoofing protections by December as part of efforts to curb rising online scams, the Straits Times reports. Singapore's Ministry of Home Affairs (MHA) said that it had issued an Implementation Directive to Apple under the Online Criminal Harms...
iphone air camera

iPhone Air Flop Sparks Industry Retreat From Ultra-Thin Phones

Thursday November 27, 2025 3:14 am PST by
Apple's disappointing iPhone Air sales are causing major Chinese mobile vendors to scrap or freeze their own ultra-thin phone projects, according to reports coming out of Asia. Since the ‌iPhone Air‌ launched in September, there have been reports of poor sales and manufacturing cuts, while Apple's supply chain has scaled back shipments and production. Apple supplier Foxconn has...

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)