16" MacBook Pro blue pixel aliasing on external display

Brought it into the Apple Store again today. Associate had heard of the issue anecdotally. He acknowledges that it's some sort of bug; whether it's software or hardware is not clear yet. I have confirmed that the problem will not present itself if About This Mac does not show the AMD graphics card listed. Apple is not aware of how to fix this issue yet, at least in a widespread manner; I recommend if you're reading this to open the Feedback Assistant app and submit a bug report directly to engineering (if this isn’t available, maybe you need to go to https://beta.apple.com/sp/betaprogram/ Hopefully they will pressure test the issue and find that it's software related, and hopefully the fix will be presented in the form of a software update.

With the following steps, I was able to reproduce the issue on all three floor machines in my local Apple Store (one out of three only showed the issue flittingly):

- Click Apple > About This Mac

     - If Graphics card section only reads the built-in Intel, open as many graphic-intensive programs as possible, such as the Adobe Suite, or even GarageBand. 

     - Close and reopen About This Mac. Make sure AMD Radeon Graphics card is shown in the list.

- Open Display preference pane.

     - Resolution > Default for display

     - Check True Tone on.

Now take note of cyan or baby blue aberration that happens on white lines on black, white type on black, or sometimes thin black lines on white. See: left vertical line of cursor, move slowly left and right. Top line of battery icon will show cyan, especially is Dark Mode is activated.

Same. Please help by also reporting the bug / hardware issue here: https://feedbackassistant.apple.com/welcome

I've also made a pair of PDFs we can use to quickly diagnose whether the issue is happening at any given moment, here: https://www.dropbox.com/sh/s0o0a54og24t634/AABJwuBIZ3ByqSY5l5O9aarSa?dl=0

It's just a bunch of boxes of varying stroke-width and position, ensuring that at least some boxes will show the issue at any given moment. Go fullscreen, don’t, move it around, and watch as different boxes show cyan sides. The black-on-white version is more difficult to see.

You can leave this PDF open as you test different things like True Tone, resolution, refresh rate, what-have you. For your own sanity as well as hopefully helping Apple squash this issue as soon as possible.

I had this same problem, I didn't see this thread so I started a new one: https://discussions.apple.com/thread/251109554

I was able to get rid of the blue pixel aliasing by deactivating Night Shift. It only seemed to appear for me when nightshift was active and the discrete GPU was on (it's always on when an external monitor is plugged in).

I'm not sure if that is what is causing your problems but it might be worth trying.

Yes you are right it's both True Tone and Night Shift that can cause this. So maybe a driver or firmware issue with the dGPU as it works on integrated ok?

There are a lot of people having heating problems with the 16'' dGPU see this thread: https://discussions.apple.com/thread/250878229

Maybe there is a bad batch of GPUs?

I am experiencing the same problem. I have another annoying issues:

• External monitor lost connection from time to time. Reconnect helps.
• Typing text in new tab in Chrome experience some input lag about 2-3 sec
• Yesterday the display (build in display) of my mac has turned off while working, but touchbar, keyboard and soundbars were still responsive.

Blue aliasing near thin lines disappears when True Tone disabled.

I am facing several Bugs with my new Macbook Pro 16 i9 AMD Radeon 5500M.

• Blue Pixel Tint on internal display with AMD on
• Drains 20w Power with AMD on when connected to external display.
• Throttles CPU with AMD on when connected to external monitor.
• Drains Battery under heavy load like video conversion in handbrake while connected to Power (140w Power?).

This MacBook AMD Combo is beta.

Will return this buggy AMD Macbook Pro 16. Shame.

I'm noticing the same behavior with Adobe button outlines, and occasional small thin black type or lines on white (images, mainly, in small quicklooks in Finder). Light blue chromatic aberration around high contrast parts. Native display on 16-inch MacBook Pro with no external monitor...

Shown here: an iPhone photo of the screen. Live dialog box below, showing light blue artifacts. Screenshot of the same dialog box, above... This proves the artifacts are a display-level bug.

I upgraded my computer from that store, and the problem just reappeared. This time the pixels are not bright cyan. They’re more of a baby blue. AMD Radeon was kicked in at the ti me, as I had opened InDesign and am connected to an external Dell monitor.

Live window vs. screenshot:

Left vertical of cursor shows same aberration at certain longitudes of the screen:

@rynop2000 are you having fan / battery issues as well? Maybe we could sidebar and cross reference what apps we have in common to see if this is software.

I visited the Apple store yesterday and was able to reproduce this issue on one out of the three 16" models that were on the floor. Graphics cards don't seem to have much to do with it, unless it's something to do with the AMD Radeon Pro 5500M 8 GB kicking in and out as supplementary to the built-in Intel. May be a manufacturing batch-specific defect.

Keep an eye on when the issue presents itself, and check `About this Mac` to see whether the AMD is listed as in-use at that moment. I'll keep this thread updated on my findings.

Off the plug for 3 hours, my computer might reach 0%. I'm not sure if that's normal. Try working off the power for a few hours and let me know how it performs.

Fanning is frequent but not as bad as it was with my 2015 model... But happens even at about half memory usage, a couple Adobe apps + Chrome open, laptop on flat surface.

P.S. Cyan pixels have returned instead of baby blue. Also experienced a one-time "tinting" of everything on my laptop screen while connected to external monitor. Toggling color profiles off and on fixed it. I think our display issues are rooted either in the AMD graphics card, Catalina, Color profile, True Tone, manufacturing defect, or any combination of the aforementioned.

Disable both True Tone and Night Shift and this issue should go away.

As others have said, this seems to be a software issue with how color tinting is applied when the discrete is in use. I can consistently turn it on and off by toggling either setting. Disappointing as I am a heavy user of night shift, but man that cyan ghost is awful.

To me, the fact I can turn it off makes it seem much more likely to be a bug in the True Tone/Night Shift functionality, but I guess it could be GPU based. I am just using f.lux for now until they fix it.

My laptop doesn't have any other issues that I have noticed, definitely nothing like what is mentioned in those other threads. The fans only spin up under really intense stress.

I have exactly the same issue. Also discovered it when connected to my UltraFine 27” display. I also noticed that when night mode and True Tone is disabled the issue goes away. Seriously hope this is a software issue ! I had a 13” MacBook with the stage light effect issue before, now this ? Looks like every MacBook they produce has issues these days...