iMac 2020, 5700XT - graphical glitch?

[dspdoc]

I too had the 5700 XT random horizontal white line issue. At first I thought I was losing my mind because it was so hard to catch. It was driving me crazy. I returned the machine and now have another on the way. I’m certain that it will exhibit the same behavior. The people voting no must simply be blinking too much. ?

I believe this is a software issue. Especially given that it cannot be captured by a screen recording and only by taking a video externally. If I am not mistaken this is inherent of a software issue and not hardware. When the iMac Pro first came out it had graphical anomalies that couldn’t be captured using screen recording methods either. I believe I recall an engineer telling me that’s a sure sign it’s software.

Some of us aren’t going to be quick to jump on BS. Apple has to patch this on Catalina too.

Here’s to Apple fixing this sooner rather than later. ?

 

[torifile]

How is that helpful, in your mind?

Your use of a comma confuses me. I’m not sure what you’re asking or why you’re having a hard time following what I’m saying.

So to be clear - I do not have the white line flicker when connected to an external display. I have not had the problem since connecting to an external display about 10 days ago.

Clear?

 

[shywizard]

I'm not sure I should even throw this out there as it may complicate things, but I haven't seen the white horizontal line while remotely logging in FROM my iMac TO my work PC using Microsoft Remote Desktop. So while I'm viewing my work PC desktop (which really is a windows PC), I haven't seen the glitch. Not sure what that means??

 

[PieTunes]

Appreciate the continued updates, @torifile, as information can prove both helpful and interesting though it seems some people fail to realize that. Why some people are getting their knickers in such a twist is interesting.

It seems evident so far that this glitch for some reason does not manifest when an external display is connected, or if you change resolutions to something other than the default. I think it’s also safe to say that we seem to have found ways to avoid the glitch from happening, but can’t find any way to reliably duplicate it on command.

I wonder what the likelihood of another beta of Big Sur being released before it goes gold, a beta that includes support for the 2020s.

 

[kkh]

I believe this is a software issue. Especially given that it cannot be captured by a screen recording and only by taking a video externally.

So, it would be the opposite. At least typically. If you can capture (screen shot, Quicktime screen recording) any anomaly, that's software. If you can not, that's hardware. Now, of course there could be something rather obscure going on (something post what we are seeing on screen) and it could still be corrected with a driver fix. Hard to say for sure.

The sharp/unrounded corners seem to be software for sure. I have been able to capture that with screen shots and screen recording. Thus far, afaik, nobody has been able to capture the white lines with software... only by pointing a camera at the screen.

 

[kkh]

It seems evident so far that this glitch for some reason does not manifest when an external display is connected, or if you change resolutions to something other than the default. I think it’s also safe to say that we seem to have found ways to avoid the glitch from happening, but can’t find any way to reliably duplicate it on command.

And, as was pointed out by @joevt, it's almost as if we need to tax the card a bit more (attach an external display or use a scaled resolution) to make the white lines go away. However, switching to a scaled resolution does not make the sharp/unrounded corners go away. Whereas attaching an external screen seems to erase both issues.

 

[dspdoc]

So, it would be the opposite. At least typically. If you can capture (screen shot, Quicktime screen recording) any anomaly, that's software. If you can not, that's hardware. Now, of course there could be something rather obscure going on (something post what we are seeing on screen) and it could still be corrected with a driver fix. Hard to say for sure.

The sharp/unrounded corners seem to be software for sure. I have been able to capture that with screen shots and screen recording. Thus far, afaik, nobody has been able to capture the white lines with software... only by pointing a camera at the screen.

Maybe I did get it backwards. Yikes! Well that’s not good then if Apple has pushed out this machine with a hardware issue. They seem to miss the ball a lot lately with QC. Not sure what their disconnect is, but what an eyesore we all have to deal with right now. In typical Apple fashion I am certain there will be utter silence regarding the issue.

 

[ADGrant]

So, it would be the opposite. At least typically. If you can capture (screen shot, Quicktime screen recording) any anomaly, that's software. If you can not, that's hardware. Now, of course there could be something rather obscure going on (something post what we are seeing on screen) and it could still be corrected with a driver fix. Hard to say for sure.

The sharp/unrounded corners seem to be software for sure. I have been able to capture that with screen shots and screen recording. Thus far, afaik, nobody has been able to capture the white lines with software... only by pointing a camera at the screen.

It is true that it would be difficult to screen capture a hardware issue but just because something can't be screen captured doesn't mean its hardware. The screen capture software could just be concealing the problem, a software equivalent to the observer effect in physics: https://en.wikipedia.org/wiki/Observer_effect_(physics)

 

[kkh]

In typical Apple fashion I am certain there will be utter silence regarding the issue.

There will not be a public announcement I'm sure, but Apple has actively reached out to me, for example, to gather tons of data on this. They do want to get to the bottom of the issue but there are many moving parts to this (including any upcoming software updates). I assume they did minimal testing using this actual piece of hardware. Why? The drivers were installed in July and AMD officially released the Pro 5700 XT in August.

 

[kkh]

It is true that it would be difficult to screen capture a hardware issue but just because something can't be screen captured doesn't mean its hardware. The screen capture software could just be concealing the problem, a software equivalent to the observer effect in physics: https://en.wikipedia.org/wiki/Observer_effect_(physics)

Correct. And, as I have mentioned before, Quicktime screen capture doesn't have an adequate frame rate to perfectly capture the screen. Doing screen shots also forces a redraw of the screen -- you can not capture the sharp corners every time, for example. Even that is a bit hit and miss but definitely reproducible.

 

[PieTunes]

And, as was pointed out by @joevt, it's almost as if we need to tax the card a bit more (attach an external display or use a scaled resolution) to make the white lines go away. However, switching to a scaled resolution does not make the sharp/unrounded corners go away. Whereas attaching an external screen seems to erase both issues.

That is such a weird thing regarding the sharp/pixelated corners. No matter what I do I can’t get them to show up. All my window corners have appeared normal since day one. I’ve tried slowly resizing the windows, changed backgrounds, True Tone on and off, dark mode on and off, resolution changes, but nothing. I even get up close and squint. They’ve always looked fine. The random white flashing line I get at default resolution has been the only visual anomaly since I got this machine.

 

[ADGrant]

There will not be a public announcement I'm sure, but Apple has actively reached out to me, for example, to gather tons of data on this. They do want to get to the bottom of the issue but there are many moving parts to this (including any upcoming software updates). I assume they did minimal testing using this actual piece of hardware. Why? The drivers were installed in July and AMD officially released the Pro 5700 XT in August.

This particular 5700XT hardware implementation is different to the others in one way, it has 16GB of VRAM, maybe that is surfacing a bug in the video driver that the 8GN versions does not. Would explain why iMac owners with the almost identical 5700 are not seeing the issue.

Possible a coincidence but I am seeing what looks like a VRAM memory leak at least according to iStat.

 

[dspdoc]

That is such a weird thing regarding the sharp/pixelated corners. No matter what I do I can’t get them to show up. All my window corners have appeared normal since day one. I’ve tried slowly resizing the windows, changed backgrounds, True Tone on and off, dark mode on and off, resolution changes, but nothing. I even get up close and squint. They’ve always looked fine. The random white flashing line I get at default resolution has been the only visual anomaly since I got this machine.

Can someone please post a photo of the ‘corners’ issue? I guess I didn’t see that when I had my machine.

 

[kkh]

That is such a weird thing regarding the sharp/pixelated corners. No matter what I do I can’t get them to show up. All my window corners have appeared normal since day one. I’ve tried slowly resizing the windows, changed backgrounds, True Tone on and off, dark mode on and off, resolution changes, but nothing. I even get up close and squint. They’ve always looked fine. The random white flashing line I get at default resolution has been the only visual anomaly since I got this machine.

Open Safari. Open Mail. Make sure that Mailboxes is displayed in Mail. Make sure you're viewing an email as well. Keep toggling between Safari and Mail. Eventually, typically, when Mail is the inactive window, you'll spot it. After that, slowly move the Mail window around and it flickers on and off.

 

[kkh]

Can someone please post a photo of the ‘corners’ issue? I guess I didn’t see that when I had my machine.

Go back to the first page of this thread? https://forums.macrumors.com/threads/imac-2020-5700xt-graphical-glitch.2251034/

 

[kkh]

This particular 5700XT hardware implementation is different to the others in one way, it has 16GB of VRAM, maybe that is surfacing a bug in the video driver that the 8GN versions does not. Would explain why iMac owners with the almost identical 5700 are not seeing the issue.

Possible a coincidence but I am seeing what looks like a VRAM memory leak at least according to iStat.

Maybe there's an issue with the RAM chips on the card? Or a bug in addressing all that RAM. Does anybody know if we can force a 16 GB card to use 8 or less? Of course the bug could be anywhere and that would not yield anything conclusive.

 

[PieTunes]

Open Safari. Open Mail. Make sure that Mailboxes is displayed in Mail. Make sure you're viewing an email as well. Keep toggling between Safari and Mail. Eventually, typically, when Mail is the inactive window, you'll spot it. After that, slowly move the Mail window around and it flickers on and off.

Thanks for those steps, when I get home tonight I’ll follow the steps and see if I can duplicate it. I’m genuinely curious!

 

[kkh]

Thanks for those steps, when I get home tonight I’ll follow the steps and see if I can duplicate it. I’m genuinely curious!

While the sharp corners and the white lines are probably not related, I'm still thinking that they may be: the bugs in rendering interface components with alpha (such as the corners) eventually overwhelm the card and we get the white lines. I also did a test in Xcode where certain window configurations do not exhibit this problem whereas others do. And while testing in Xcode, I saw the white lines appear a handful of times when the windows I was testing exhibited the corner issue. Still, that may be misleading and coincidental.

 

[dspdoc]

Go back to the first page of this thread? https://forums.macrumors.com/threads/imac-2020-5700xt-graphical-glitch.2251034/

Wow ? that is ugly! C’mon Apple. Enough of the slop. This isn’t your DNA.

 

[kkh]

Thanks for those steps, when I get home tonight I’ll follow the steps and see if I can duplicate it. I’m genuinely curious!

Wait, so, I thought you saw this, too? Or so you said! https://forums.macrumors.com/threads/imac-2020-5700xt-graphical-glitch.2251034/post-28807346

 

[kkh]

Wow ? that is ugly! C’mon Apple. Enough of the slop. This isn’t your DNA.

Apple is famous for the friendly rounded corners, right? Or, was. So, that really feels like a bad ding on an otherwise beautiful machine. Have to add: love the nano-texture glass by the way.

 

[haddy]

Possible a coincidence but I am seeing what looks like a VRAM memory leak at least according to iStat.

I think that you are right, that this is the problem. I am very tempted to order the 2020 iMac with the 5700 card
but will wait for a wee while just to see what Apple comes up with.

 

[dspdoc]

Apple is famous for the friendly rounded corners, right? Or, was. So, that really feels like a bad ding on an otherwise beautiful machine. Have to add: love the nano-texture glass by the way.

Being someone with pretty severe OCD/perfectionism, it’s extremely difficult for me to see these sorts of issues. Especially knowing this is most likely the last ‘hoorah’ for the Intel iMac. I just wish Apple would put a little/lot more time into QC and testing. How’d this slip by them? Then again, maybe they just thought it would slip by us...? ? ??‍♂️

 

[PieTunes]

Wait, so, I thought you saw this, too? Or so you said! https://forums.macrumors.com/threads/imac-2020-5700xt-graphical-glitch.2251034/post-28807346

That one time for sure, sorry about the mixup! I wasn’t sure at the time if it was able to be replicated, the flashing white line kept popping up with more frequency. I tried to duplicate the corner pixel issue but couldn’t anymore. With these steps it’s something I’ll definitely have to try again.

I wish there were any seemingly reliable ways or steps to duplicate the white line.

 

[kkh]

Possible a coincidence but I am seeing what looks like a VRAM memory leak at least according to iStat.

It's been years since I had iStat installed. How specific is that error? What information does it show you?