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iMac (M1, 2021) Display Issue
- Thread starter ButWhyY
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Retroworldnews
macrumors 6502
Side note you M3 iMac screen is more whiter, brighter or warmer ?? Just like iPhone, whereby both users own the same model of the iPhone but the screen , some look whiter whereas some look warmer.
codehire
macrumors newbie
I have an iMac M1 that's at least 3 years old as far as I can remember. At the end of September 2025, I started experiencing a flickering screen. I even tried taking it apart myself using guides from iFixit and YouTube. I removed the display from the iMac M1 unit, but unfortunately I didn't see anything unusual there. What I mean is that a lot of people say it's a burnt flex cable or something similar, but I'm not sure which cable that would be (it might be inside the display itself, which obviously I can't open up).
Anyway, here's a small tip from me if your screen is just showing lines and hasn't started flickering yet. Usually, when the flickering happens, you'll feel that one of the corners (either top or bottom) gets warm. Try directing some airflow to that area, as it can help cool down the flex cable and prevent the flickering from showing up.
Anyway, here's a small tip from me if your screen is just showing lines and hasn't started flickering yet. Usually, when the flickering happens, you'll feel that one of the corners (either top or bottom) gets warm. Try directing some airflow to that area, as it can help cool down the flex cable and prevent the flickering from showing up.
Retroworldnews
macrumors 6502
One thing , your M1 have two thunderbolt or 4 thunderbolt?
Actually my M3 , well at first the lines appear on the bottom of the screen. Never flickering those lines. Just static lines there. Later like after few months or so. Lines increase also at the bottom but this time those new lines flickering. Still can use as the lines never cover the mid screen. Of course come see videos full screen you tend to feel .... as the flickering lines below.
codehire
macrumors newbie
Retroworldnews
macrumors 6502
Same for my M3 , I not sure those claim theirs never have this flickering problem maybe their is 4 thunderbolt? I happen to find out model with 4 thunderbolt have two additional fans inside the iMac.
I have an M1 2021 iMac that I bought in January 2024 so it's about 2.5 years old now. Obviously, this issue concerns me but as of today, I don't see any issues with my screen. I'm wondering a couple things. Is this something that is common or are there a good percentage of M1's out there that are over two years and have not experienced this issue. I'm guessing, and it's my hope, that while this is a known issue, that it's not all too common. I'm also wondering if there's any timeframe or style that is more susceptible to this. My unit is the 8 core CPU/GPU model with two fans and ethernet. It was probably built in 2023 just before they discontinued that model. When I bough it, Apple was no longer selling it - Only refurbished. I bought mine at Costco, which came with the two year warranty, but of course, that's over at this point.
codehire
macrumors newbie
Glad to hear it's still working fine on your end, and I hope this is really just a small minority of cases. Although I'm sure there are plenty of people out there experiencing this who aren't here.
I might want to ask, is the air circulation in your room consistently kept cool?
I live in a tropical country, and there's a rumor going around that this flex cable is extremely thin while carrying a fairly heavy load of around 50v current (though I'm not totally sure about that), and with the hot weather here, it speeds up the wear and tear on that flex cable.
Because in my case, when the horizontal lines first showed up, I always had the AC running in my room and it was fine, at least usable, but when I turned the AC off, the screen started flickering and the top left corner of the screen felt very hot, maybe over 80 degrees.
Two things about heat. First, my house is air conditioned and I rarely let it go over 80 degrees. Usually is under 76 degrees. Second, I’m not a power user. I don’t think I’ve ever heard my fans spin up and I know I’ve never had any times where the computer was working hard. I mostly do the basics like web surfing, email, one small spreadsheet. The most taxing program I run is Turbo Tax. So I’m hopeful that if it’s a heat issue that my use habits may buy me more time. I’d like to get at least 5 years out of it.
Retroworldnews
macrumors 6502
my M3 also never do any taxing stuffs like video editing or even playing games. I just use for simple work , doing marketing and email that it. Never have anything accidentally hit the iMac. All along sit firmly on the desk. I also weekly clean the screen , wipe around with a duster. And just after one year or usage suddenly these " lines, flickering appear on the bottom of the screen just like that.
