iMac 2020, 5700XT - graphical glitch?

[ADGrant]

Well I returned mine (with a 5700 XT) and ordered a new one with the 5700. I haven’t seen the white line (yet at least) but I have seen a flickering of the FaceTime upper right corner. But once only and never after that. Oh well... my best guess is : software problem for all 5xxx graphics cards PLUS a hardware/driver-specific bug for the XT version of the graphics card.

I am fairly confident that the flickering corner is a software problem, probably in the window manager. I am fairly confident that it will be addressed since it seems simple enough to reproduce. I am less confident about the white line issue.

I think there is a good chance other Navi equipped iMacs have similar issues if these are indeed software issues.

My new 5700XT arrived today so I should get a chance to experience the fun tomorrow.

 

[torifile]

I spent all day on Zoom meetings today. Staring at the screen (the internal display). Not once did I notice the white lines. I still have my secondary display connected. I'll be on Zoom all day again tomorrow so I'll disconnect and see if there's any difference.

 

[shywizard]

So are you keeping it? How frequently were you seeing the lines in the regular "Retina" mode?

I still have a few days to make a decision.
Curious to know if anyone has the 2020 iMac with the 5700XT and isn't having the issues we mentioned. If it was software related, it would affect everyone I would think. But then again, the fact that it went away by changing resolutions tells me that software can probably fix the issue.

So I guess 2 questions for the forum:
1. Does anyone have the 2020 iMac with 5700XT and they are NOT seeing the horizontal white line
2. Can we confirm that by simply getting the 2020 iMac with the regular 5700, the horizontal line doesn't happen

That will help me determine what I must do.

 

[Nermal]

And if I’m not mistaken, the current beta of Big Sur isn’t compatible on 2020 iMacs yet correct? Including the most recent beta 6? I’d really like to know if the white line glitch happens there.

As far as I'm aware, there is no beta 6 yet (it doesn't show up in my developer account and I don't see it listed on the MR front page).

 

[ninja2000]

Sorry I am late to the party guys, been busy at work. I have not noticed any flickering on the 5700 in my machine

 

[anthony13]

today I started also noticing the corner edge of my activity monitor window doing the same edge problem as noted above.

 

[creativityrules]

I created a poll to see if the white horizontal line flickering is unique to certain GPU's:

iMac 2020 27" white horizontal line flicker poll

With no additional displays connected and in native retina resolution, are you experiencing the while horizontal line flicker on the display? Example of flickering:

forums.macrumors.com

 

[costica1234]

I created a poll to see if the white horizontal line flickering is unique to certain GPU's:

iMac 2020 27" white horizontal line flicker poll

With no additional displays connected and in native retina resolution, are you experiencing the while horizontal line flicker on the display? Example of flickering:

forums.macrumors.com

Great idea! A moderator should pin your thread at the top of the forum for increased visibility.

 

[ADGrant]

today I started also noticing the corner edge of my activity monitor window doing the same edge problem as noted above.

What about the white line flicker?

 

[kkh]

Apple just reached out to me. Missed the call but got an email as well. They want more details on what I reported on this on the Apple forums. I will try to chat with them tomorrow. I will report everything we all have collectively experienced thus far.

 

[creativityrules]

Please cast all your votes into the poll I created. I think it will help highlight the hardware specific issue for Apple to reference.

 

[torifile]

Please cast all your votes into the poll I created. I think it will help highlight the hardware specific issue for Apple to reference.

Since this thread is so large, I added the poll here. Good idea.
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[shywizard]

FYI. To follow up on my testing.......I changed the iMac Display resolution from DEFAULT to 2048x1152 and the horizontal line glitch hasn't happened since. It's only been a day and I was out most of last night, but sure hope were onto something here. It would be great if a few of you could also change your display resolutions and see if the horizontal white line goes away. (the corner issue still remains).

No horizontal glitches all day. Resolution change fixed it.

 

[pmiles]

Just saw this posted on the Apple Forums. Have to manually click play to see it. Very short video. That certainly would be distracting if it occurred frequently.

 

[Macral]

Edited: my bad, didn't notice the update.

 

[jamespb78]

Didn't that update come out a week or 2 back?

 

[creativityrules]

Didn't that update come out a week or 2 back?

Looks like it is from Aug-12: https://support.apple.com/kb/DL2049?locale=en_US

 

[Paul Cordingley]

I've been on my new i7/2TB/5700XT solidly for the last two days (all day for work), and except for during the initial setup screens, have not seen a single flash or white line. In dark mode.

During setup I saw a few instances of a white horizontal line. Not seen since.

As for the rounded corner issue - yes, I can replicate that - it's not distracting for me at all, but I am very confident this is all driver related and will be fixed.

 

[ErikGrim]

Wow. That would annoy me to no end. Fortunately no such issues with my 5700XT 16Gb 8-core i7.

 

[shywizard]

I've been on my new i7/2TB/5700XT solidly for the last two days (all day for work), and except for during the initial setup screens, have not seen a single flash or white line. In dark mode.

During setup I saw a few instances of a white horizontal line. Not seen since.

As for the rounded corner issue - yes, I can replicate that - it's not distracting for me at all, but I am very confident this is all driver related and will be fixed.

Interesting. Many of us who see the issue have the i9.
Could the processor speed play into this?? Everyone, please use the poll so we know what processor speed you have.
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Wow. That would annoy me to no end. Fortunately no such issues with my 5700XT 16Gb.

You have the i7 or i9?

 

[jerome444]

Interesting. Many of us who see the issue have the i9.
Could the processor speed play into this?? Everyone, please use the poll so we know what processor speed you have.
[automerge]1598520719[/automerge]

You have the i7 or i9?

No I had the i7 and had both problems. I returned the Mac with the 5700XT and ordered one with the regular 5700 and have no issue.

 

[Conradiminja]

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[torifile]

Just a question for everyone using an external display. I've noticed that a lot of people that has the flickering issue on external displays connect it with the Apple Digital AV USB-C dongle.(https://www.apple.com/au/shop/product/MUF82ZA/A/usb-c-digital-av-multiport-adapter)

Is there anyone that has their display connected with only usb-c (no dongle) or any other dongle types and still experiences the flickering? Just so we know if the dongle is somehow responsible the flickering. (Got my Benq PD2700Q connected to my MacBook Pro 16" 5500m with the usb-c digital av dongle and experience the flickering a lot)

What people have flickering with an external display? I had flickering with *no* external display and no flickering with an external connected via a USB-C to DisplayPort cable.

I wonder if you’re conflating this iMac issue with the MBP issue. They seem different.

 

[RossH51]

Most of the white line glitches I get seem to match the vertical positioning of the mouse pointer.

I would agree with this. Consistent with the occasional flash that I see usually to right of active window and level with pointer.
It is very occasional for me so not a major issue. Hopefully addressed with software update.

 

[tommiart]

At least now there are some videos about it. we might get it solved quicker