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iMac 2020, 5700XT - graphical glitch?
- Thread starter torifile
- Start date
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I received my new 2020 iMac a week ago. I'm also seeing a white single HORIZONTAL LINE flash mid-way up the screen. My iMac has the AMD Radeon Pro 5700 XT 16 GB graphics card.
This mysterious line only flickers a few times per day (so it's not super annoying). But I can't figure out what is causing it. I've tried to replicate it by changing resolutions, true tone, etc but it just happens so infrequently and randomly....my efforts have been futile.
I'm glad I'm not the only person having this issue. FYI, I called Apple to report the issue and they were clueless that this was happening. Best guess was that I should reset the P-RAM (which I did and it didn't solve the issue).
This mysterious line only flickers a few times per day (so it's not super annoying). But I can't figure out what is causing it. I've tried to replicate it by changing resolutions, true tone, etc but it just happens so infrequently and randomly....my efforts have been futile.
I'm glad I'm not the only person having this issue. FYI, I called Apple to report the issue and they were clueless that this was happening. Best guess was that I should reset the P-RAM (which I did and it didn't solve the issue).
They even made me reinstall macOS to no avail : well, it's been there even BEFORE macOS was initially installed.
YES, YES, YES. Also contact online tech publications, if you have contacts there, that will make Apple react (hopefully)
Hard so say, I've already seen these a couple of times today after like 2 hours of using the iMac. During the initial setup process, many times. But the other glitch (square window corners) is there all the time. The easiest way to see it is to launch FaceTime : the upper right black corners oscillates between square and round all the time. I will have the iMac replaced, but I'm pretty sure this is a software bug (like, AMD graphics card driver bug) and the new iMac will behave the same. If Apple doesn't solve this problem it will quickly cost them a fortune... and harm their reputation for reliability/high end systems even more (it's pretty damaged already). My take is that this display bug is related to a problem with the alpha channel used for drawing round corners. But this doesn't explain the white lines, though.
Too funny, I didn't think I had the 'square window corner' issue. But then I launched FaceTime and was able to see it.
So I have both issues like you. It's a shame because I spent a fortune on this iMac and other than this graphic glitch, it's working really well (extra extra snappy). Not sure how Apple missed these graphics issues when testing out their computer/configurations. I wonder if the regular 5700 (NOT XT) has the same issue? When I called Apple to inform them of the horizontal white line issue, they also suggested I take it in for a repair (but clearly it's affecting a lot of people, so repair isn't going to help).
So I have both issues like you. It's a shame because I spent a fortune on this iMac and other than this graphic glitch, it's working really well (extra extra snappy). Not sure how Apple missed these graphics issues when testing out their computer/configurations. I wonder if the regular 5700 (NOT XT) has the same issue? When I called Apple to inform them of the horizontal white line issue, they also suggested I take it in for a repair (but clearly it's affecting a lot of people, so repair isn't going to help).
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It's really hard to say. It seems to happen without rhyme or reason. One moment I notice it while browsing Safari, another moment it's when reading an email an hour later, then a minute later it happens again, then I don't see it the rest of the day. I used my iMac about 4 hours last night and didn't notice it at all, but I saw it once in the morning. On top of this, who's to say it is happening and I just straight up haven't noticed it since it happens so fast or it happens in an area of the screen that's bright so I don't see it.
I haven't seen the white line, but, I've had my new iMac for 5 days now, transferring stuff over from old iMac, and I think I see that square corner thing on the FaceTime window--looks like a tiny sharp point coming out of the curved corner? I can only notice it on the upper left corner, and I do not see it on the Finder window...
Sorry I don't understand what you mean by "even BEFORE macOS was initially installed". It should have been installed on you iMac before you received it.
Yeah, it's like the rounded corners of the windows become squared off with a slightly different shade of pixels. You have a 5700XT?
That seems like a separate issue from the white lines to me. I think the window corners are a software issue. Hopefully the white line flickering is too.
What confuses me is why a software issue would affect only the 5700XT. It isn't that different to the 5700 or even the 5500.
Good questions indeed. Maybe there's something specific to the 5700XT that causes this to come up. I haven't seen anyone with a 5700 chime in yet saying they're experiencing it. And @torifile wasn't able to duplicate the flashing line in Windows which leads me to believe it's most likely something software related. I'm going to send Apple some feedback regarding this.
And also as others have said, there have been absolutely no other issues with my machine. Everything is perfect and its performance is quite stellar. Blows the pants off my 2017 with the 580 video card. It just bugs that this... bug, is even here!
I’ve had 2020 5700XT 10 core IMac for 10 days I haven’t seen this flashing white line. I’m using dark theme so I’m pretty sure I would have by now if it was doing it on my iMac
I have had the same white line issue since the day I received mine. 5700XT.
Very infrequent. Seemingly only appears during a touch down event on my mouse.
Only ever noticed it on the desktop itself, never over a window.
Only to the left of the window on the desktop around the centre of the screen IIRC. ]
Hopefully this suggests it is a software issue.
**EDIT**
Noticed it happening both sides of a window. Not just mouse down but mouse moved too.
Very infrequent. Seemingly only appears during a touch down event on my mouse.
Only ever noticed it on the desktop itself, never over a window.
Only to the left of the window on the desktop around the centre of the screen IIRC. ]
Hopefully this suggests it is a software issue.
**EDIT**
Noticed it happening both sides of a window. Not just mouse down but mouse moved too.
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New poster here. I have also been noticing this horizontal white line and have been searching for a solution. It happens a few times a day and at first I thought I was seeing things. I haven’t noticed this glitch in boot camp, so I think it is definitely a MacOS issue. I have no issues while pushing the GPU in games and benchmarks. I hope there is a fix for it soon.
After I got the iMac, I took out the Apple RAM and put in 128 GB from OWC. I also have True Tone turned off.
27-inch iMac with Retina 5K display |
With the following configuration: Nano-texture glass 3.6GHz 10-core 10th-generation Intel Core i9 processor, Turbo Boost up to 5.0GHz 8GB 2666MHz DDR4 memory Radeon Pro 5700 XT with 16GB of GDDR6 memory 2TB SSD storage Gigabit Ethernet Magic Trackpad 2 Magic Keyboard with Numeric Keypad - US English Accessory Kit |
I have noticed over windows to the left and right of my current window. It’s possible that it only occurs on touchdown but I haven’t been able to tell for sure. I’m positive it’s software given my experience in Windows and the screen flickering on macbooks that was cleared up by a software update. Even if it were “hardware” many things can be fixed by firmware updates.