Would appreciate if someone else would switch to 2048x1152 resolution for a day or two and see if the horizontal line issue goes away. Apple wants to know, but nobody other than myself seems to be testing that theory. For me, it fixed the issue.
Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
iMac 2020, 5700XT - graphical glitch?
- Thread starter torifile
- Start date
- Sort by reaction score
I tried it for ~4 hours this weekend and did not see the white lines. But sometimes 4 hours goes by without me seeing them at Default For Display. Anyway, so, an incomplete test as such. However, the rounded corner issue is still present at 2048 x 1152 so clearly something is still going wrong even at that resolution.
If there is any tearing, it’s not very visible to me on the 2020 but I loaded recovery mode on my 2017 and it has a slight but noticeable stutter when moving windows around. Makes sense that this would happen in a low level mode when there isn’t anything like acceleration and just base drivers are loaded. It seems far more pronounced on the 2017 versus the 2020 at least to me.
Ok, so what you’re saying essentially is that you’re unable to spot the difference between gpu drivers fully loaded and not loaded at all (in Recovery mode). And you got the audacity to tell people how minor the line glitch is or isn’t and how should or shouldn’t people feel about it. Wow! Welcome to MacForums, dear f me lol
You're quite welcome. And yes I can spot the difference, though the tearing as is not very noticeable or anything I really care about in recovery mode. I'm used to gaming where there's a heavy mismatch between high FPS and Vsync being disabled when the entire screen is moving around and being redrawn, not where I'd have to shake a window around rapidly to get some slight tearing, especially in a mode where it's no big deal. Honest question, is this your first Mac? Do your previous experiences with recovery mode show no tearing at all?
And nowhere in my previous posts have I proclaimed the flashing white line glitch should be considered minor by everyone. I've experienced it since day one, and was the second one to chime in in this thread before you even joined the forums. I like many others hare hoping that it's able to be fixed with a software update and there isn't much else we can do other than wait, short of returning the machine.
The random flashing white line is the only issue I've experienced and for me, it's not near enough for me to want to return the machine. If Apple can't correct it with a software fix, I'll take advantage of Apple Care. If it's more pronounced and frequent, as you've stated it was for you, as well as the other graphical anomalies you're experiencing, plus the loud fans, it's entirely possible you got a dud of a machine which if I were in your shoes would make me very unhappy. Are you leaning towards keeping it and still giving Apple the money for it, or will you be returning it?
Cheers.
Sounds plausible, but I'm no hardware (or software) engineer. Sounds like a good troubleshooting step. I just switched my resolution to 2048 and will try it out for a few days. I'm really curious how it fares in the evenings, with my darkened dynamic wallpaper plus dark mode make the flashes far more pronounced. I don't recall seeing it during the day but that doesn't mean it hasn't happened!
Interestingly, wouldn’t it make sense for Apple to send a problematic “white line glitch issue” iMac 5700XT that has been returned for that reason to their technical department for assessment and debugging?
In the days of yore when you would get a new Mac out of the box the first thing you did was reisntall the OS from the discs that came with it. It was on the advice from Apple tech support when you would get kernel panics or other problems on the first day. The reasoning they gave was that they used the same master install discs at the assembly facility and these could get corrupted unknowingly .. so many machines were sent out with messed up operating systems. It is possible we are seeing something similar with the software for the graphics system.. Just a thought..
Was on the phone to a supervisor at Apple support today for an unrelated issue and happened to ask if she had heard anything about the flickering lines on the 5700xt.. She said she was unaware of this new glitch and asked me what it was. I told her about what we are experiencing and pointed her to the Apple support forum threads about this (she isnt allowed to go to 3rd party sites at work but I told her to check out the MacRumors forum when she could for more). She spent a few minutes reading the Apple forum threads and was genuinely concerned. She said she was going to tell her staff and those up the chain since it looked like they were going to have to be prepared to deal with this issue. Considering this computer is only a few weeks old they can expect more cases.. So, they know but they dont really know I guess..
Was on the phone to a supervisor at Apple support today for an unrelated issue and happened to ask if she had heard anything about the flickering lines on the 5700xt.. She said she was unaware of this new glitch and asked me what it was. I told her about what we are experiencing and pointed her to the Apple support forum threads about this (she isnt allowed to go to 3rd party sites at work but I told her to check out the MacRumors forum when she could for more). She spent a few minutes reading the Apple forum threads and was genuinely concerned. She said she was going to tell her staff and those up the chain since it looked like they were going to have to be prepared to deal with this issue. Considering this computer is only a few weeks old they can expect more cases.. So, they know but they dont really know I guess..
Last edited:
I would also love to know if switching to 2048 resolution also works with no glitch as that’s likely to be the resolution I’d prefer to use. If you can report back, I’d appreciate that.
Wow that’s good - at least there’s some acknowledgement that they’ll look into it!
I told Apple (Australia) directly over the phone the other day about the glitch being experienced by lots of new iMac 5700XT owners which is why I cancelled my order and why I believe it has potential for lost sales. That should get their attention.
Now that some time has elapsed since well known Apple hardware reviewers have been using their high end iMacs with the 5700XT, have any of them made mention of the flashing white line glitch at all recently? What's the likelihood that not one of them is experiencing it?
The only YouTube video I've found so far where the iMac 2020 5700XT owner (reviewer) has seen it for himself and openly discusses it during the video is from Tally Ho Tech. Also in the comments he responded with "I never seen it during set-up Just randomly happen when I first used it"
I also reached out to Max Tech (YouTube channel) and he responded that he hasn't experienced the issue.
Last edited:
Well when you also consider that apparently there is no horizontal line glitch when running Windows, it certainly suggests a software issue.
The corners problem is definitely a software issue and has been seen on other iMac GPU configurations.
Thank you......I also rang Apple AU Sydney and logged a concern.....even though I haven't yet bought a 2020 iMac
Can I suggest that everyone with this issue please go to the official Apple forums (link below) and click the "I have this question too" option directly under the first post. I suspect the Apple team pays close attention to the vote count and prioritises software fixes accordingly.
discussions.apple.com
White Horizontal Line on new 2020 iMac wi… - Apple Community
Noice one.Great thinking 99. The above video is quite good.Thank you......I also rang Apple AU Sydney and logged a concern.....even though I haven't yet bought a 2020 iMac
NoBS fanboy stuff. Just saying how it is.
On another note. If people are not getting glitches with changed resolution that means it's software?
There is no 10.15.7 beta right?
I don't know of very few posts over at Apple Discussions website, this here https://discussions.apple.com/thread/251730390?login=true is the only thread I could find and participated in. To really gain traction w/ the issue please post over there as well.
