back to article Why your external monitor looks awful on Arm-based Macs, the open source fix – and the guy who wrote it

Folks who use Apple Silicon-powered Macs with some third-party monitors are disappointed with the results: text and icons can appear too tiny or blurry, or the available resolutions are lower than what the displays are capable of. It took an open source programmer working in his spare time to come up with a workaround that …

  1. TRT Silver badge

    Buy that person a beer!

    Now, is there a way to stop Apple machines from throwing a hissy fit at the connection of a non-HDCP device to a chain on the video output? It causes havoc with our hybrid meeting systems video feed.

    1. TeeCee Gold badge

      Re: Buy that person a beer!

      Yes. Buy your kit from a company that doesn't have its tongue up the arse of the US film industry.

      Or don't do this until the iMeeting system comes out ($299,999,999 plus tax. Requires iNternet.)

      1. kurkosdr

        Re: Buy that person a beer!

        A company doesn't have to have its tongue up the arse of the US film industry to support HDCP. If you want your device to play premium content in 1080p or higher, it needs to support HDCP. It's why Desktop Linux only does Netflix up to720p.

        Yes, an OS could switch between HDCP and non-HDCP, but most devices just enable HDCP when the device is connected to avoid making a non-seamless switch when they have to play premium content.

  2. Ashto5


    See a problem

    Fix a problem

    Total dev god ….

    Thank you to the dev

    1. big_D Silver badge

      Re: Fantastic


      I have a 43" 4K LG display and a Mac mini on order. Hopefully, that should work fine (100% scaling), but you never know...

      1. Anonymous Coward
        Anonymous Coward

        Re: Fantastic

        I'm in London right now, but as soon as I get back home later this week I'm going to try it.

        I have the LG 43" monitor (43UN700-B) which already took some convincing to work on the last Intel MacBook (and many, many feedback entries which, to be fair, seemed to have resulted in different approaches but never one that *solved* the problem).

        On a Mac mini M1 it's taken a bit of tweaking too, so this may just be the ticket.

  3. Michael Hoffmann Silver badge

    I worry that...

    ... Monday's El Reg article will appear with

    "BetterDummy author served with cease and desist by Apple Legal Eagles"

    (yeah, it'll be snazzier when actual El Reg folks write it - but just as exasperating)

    Hope I'm wrong!

    1. TRT Silver badge

      Re: I worry that...

      "Apple throws BetterDummy out of pram and goes back to just sucking"?

      1. Missing Semicolon Silver badge

        Re: I worry that...

        Yeah. The undocumented APIs will stop working on the next update. Somebody at Apple decided that using non-apple displays needs to be crappier than a "proper" Apple one.

    2. Zippy´s Sausage Factory

      Re: I worry that...

      I think if that were going to happen, they'd have sued the developer of SwitchResX, which does much the same thing (albeit paid for) and has been shareware for about a dozen years now.

    3. Anal Leakage

      Re: I worry that...

      Only in your dreams.

  4. Old Used Programmer


    An M1 Mac running iOS can't do what a $35 Rapsberry Pi running RPiOS can, set custom display timings and parameters.

    1. Totally not a Cylon

      Re: Amazing....

      Down voted for not understanding that a Mac is for doing work on; it just works....

      Whereas a Raspberry Pi and other SBCs are for playing with and tinkering with.

      The Mac is designed to protect itself from 'User Fiddling' whereas the Pi is designed to be easy to fiddle with, break and then fix....

      1. Headley_Grange Silver badge

        Re: Amazing....

        "Down voted for not understanding that a Mac is for doing work on; it just works...."

        The "it just works" thing stopped working for me some time ago and gave up the ghost completely with Big Sur. iTunes sort of worked, but Music doesn't - Airplay is buggy, smart playlists don't synch with devices, etc. The DVD app has no controls for adjusting colour, contrast and sound - or indeed anything at all. And as for the the iPod app - it's a clusterfuck that seems to have been designed by people who have never listened to podcasts and hate anyone that does.

        As the article notes, they seem to be using iPhone/iPad app code for the Mac which results in dumbed-down apps at best and steaming piles of buggy shite at worst.

        1. Evilgoat76

          Re: Amazing....

          Maybe you should look at what PIs are appearing in. The days of them being a fun tinker project are long gone. Hence why the compute modules exist. We use then in fixed 4k CCTV terminals so in this case, yes they DO work much better than a Mac

          1. TRT Silver badge

            Re: Amazing....

            They do. Thanks to the tinkerers who make them work better.

            1. Dave559

              Re: Amazing....

              "They do. Thanks to the tinkerers who make them work better."

              There was some guy who once said:

              Here's to the crazy ones, the misfits, the rebels, the troublemakers, the round pegs in the square holes... the ones who see things differently -- they're not fond of rules... You can quote them, disagree with them, glorify or vilify them, but the only thing you can't do is ignore them because they change things... they push the human race forward, and while some may see them as the crazy ones, we see genius, because the ones who are crazy enough to think that they can change the world, are the ones who do.

              If that's not an ode to tinkerers, I don't know what is (Three cheers for the tinkerers!).

              Unfortunately, I seem to have forgotten who it was. Sometimes, it seems, so have Apple…

          2. juice

            Re: Amazing....

            > Maybe you should look at what PIs are appearing in. The days of them being a fun tinker project are long gone

            To be fair to the original poster, I think that's missing the point somewhat.

            The Raspberry Pi inherited the spirit of the original BBC Micro, in that it was intended to be used as the base for interesting hardware integrations. By it's very nature (and with the caveat around the IP restrictions for the hardware they're using), it's designed to be flexible and configurable.

            Conversely, Apple makes machines which are intended to be black-box devices which all integrate into the great Apple eco-system. You pay the Apple Tax, buy the thing, settle it in next to all your other Apple things and it Just Works.

            Or at least, that's the theory. Results may well vary, especially if you're trying to use Apple devices with non-Apple things.

            And with their ongoing move towards entirely in-house technology, that may well get worse; in the past, they've been at least somewhat constrained by the fact that they were using components from other companies.

            (Which isn't to say that Apple won't adhere to industry standards. But the level of effort they put into making their technology compatible with third party systems may well dwindle. After all, it'd work so much better if you just bought another Apple device...)

        2. Tachisme

          Re: Amazing....

          Agreed. I used Macs almost exclusively from 2006 until 2019, but finally gave up as it was increasingly apparent they are now an afterthought in Apple’s product range,

        3. Anonymous Coward
          Anonymous Coward

          Re: Amazing....

          >The "it just works" thing stopped working for me some time ago and gave up the ghost completely with Big Sur.

          Yep me too, the other half's MAC book Pro was upgraded to KDE Neon, required a driver to be installed, the camera I think it was, or maybe WiFi, I don't remember, having to hunt down a driver is pretty unusual nowadays on Linux but has been working well over the last couple of years. She just hated Apples OS and coming from a 100% windows world was sceptical about Linux. But she gave it a try and guess what, it does the job and she is surprised by how easy it is to use.

      2. oiseau

        Re: Amazing....

        The Mac is designed to protect itself from 'User Fiddling'...

        Don't be daft.

        It's not Friday yet. 8^/

        True to its decades long style of doing things, Apple wants to keep Mac owners from using a high definition extrnal monitor with the OS's HiDPI unless you are using their Apple branded and tear jerking expensive stand-less monitor.

        That's all there is to it.

        Absolutely no user fiddling needed if Apple had not done this.

        You'd just plug you the reasonably priced monitor of your choosing and it would just work.

        Get it?


        1. Anonymous Coward
          Anonymous Coward

          Re: Amazing....

          To be fair, only the latest 43" LG monitor I bought has had some issues. For the rest I am enjoying the fact that I can land in any random location and generally have immediate access to printers, and I have been using a PC mouse for ages because I can't get on wth their smart mouse - and that just works too.

          The only problem I have had with the MacBook I'm using now is that I had to install BetterTouchTool to create some dead zones on the infernal display they replaced the function keys with - that was an interesting experiment, but not very successful.

          Add to that that MacOS and i(whatever)OS generally talk open standards and so happily integrate with a Linux back end and no, I can't agree with you. For most of what I want it to do it works quite well with peripherals.

      3. Michael Strorm Silver badge

        Re: Amazing....

        "it just works...."

        Er, the entire problem in the parent story is that it *doesn't* "just work" as expected, let alone desired- quite the opposite.

      4. Jaybus

        Re: Amazing....

        My experience is that I plug in two monitors (of any type) and ... it just DOES NOT work.

    2. Paul

      Re: Amazing....

      Some butt hurt Apple fans didn't like the parent comment, and probably won't like this one.

    3. big_D Silver badge

      Re: Amazing....

      Only until you update the Pi. I have a UWD display and the initial RPiOS showed fine. Ran updates, restarted and it can only do 1280x1024 (not 3440x1440).

      Edit: I take that back, the latest update and it is working again. But it seems tempramental.

      1. oiseau

        Re: Amazing....

        ... working again. But it seems tempramental.

        For what it cost me, it can be as temperamental as it wants to be.


  5. Anonymous Coward

    Apple is probably one of the biggest innovators, always willing to push the envelope and design things better.

    Hilarious. I wish I could catch one of this guy's stand-up shows. I bet he has the audience in stitches the whole time.

    1. Nifty

      He's trying to tiptoe around the behemoth.

    2. Anonymous Coward
      Anonymous Coward

      Apple won't "push the envelope" unless they first give it round corners.

  6. T. F. M. Reader

    NextSTEP (pun intended)

    Make M1 laptops work with more than one external monitor of any kind. Preferably in such a way that it will "just work".

    1. Tom 7

      Re: NextSTEP (pun intended)

      The trouble with 'just work' is it frequently makes the wrong assumptions about what 'just work' means to you.

      1. Muppet Boss

        Re: NextSTEP (pun intended)

        Disclaimer: only applies to genuine Apple products. If genuine Apple products do not work, you are using them wrong.

        1. chris street

          Re: NextSTEP (pun intended)

          Using it wrong - or holding it wrong?

  7. Occams_Cat

    Browsing the web for help whilst on hold to Apple suport for a 3rd time in a day and found this article. Very helpful.

    I have a 2020 M1 MacBook Air and upon arrival it worked flawlessly with my Samsung G9 49" ultrawide screen and my 4K BenQ screen. Roll on 6 months and after the last Monterey update I can now only get the M1 to pump out 1080p over any connection to any screen, with no options to scale or change the resolution other than to pick resolutions lower than 1080! Re-installed the OS, tried severl expensive cables USBC/HDMI/DP and all have the same issue.

    The fact that it worked perfectly well upon launch with whatever drivers they were using and now Apple have completely borked it up and don't seem to have a fix after so long, is enourmously embarassing for Apple.

    1. Warm Braw

      embarassing for Apple

      History suggests they only even do acknowledgement quietly and at a much later date.

    2. Missing Semicolon Silver badge

      As i said above. Somebody took the code out, because who needs it? Buy a "proper" monitor, /s

    3. kurkosdr

      IMO Apple has lost the high ground when it comes to software. Tim Cook is a hardware guy, so he presumably pushes the company more towards hardware development. Sure, this has given us some impressive Apple hardware, but the software is suffering.

      The fact that Apple fans make blog posts complaining about the state of Apple software is telling. Just search for "apple don't order the fish" and "apple has lost the functional high-ground" to see what I mean.

      Which is a pity, because attention to software was what used to set Apple apart from the rest. Competing on hardware isn't that much of a differentiator, because the rest tend to catch up.

      1. Headley_Grange Silver badge

        I think it's that they care more and spend more on new stuff and making a big splash at their annual bash. Once stuff is released then it seems that support is dumped on a dept with not enough money or people while the rest of the company focuses on the-next-big-thing. There are problems with many apps in both Mac and iOS that have been there for at least ten years and not addressed, but "we added a couple of lines to the UK Street Address template in Contacts" or "we've updated iPhone Contacts so that you can set ringtones for groups" aren't the sort of stuff that's going to get Tim a standing ovation in September.

    4. Geez Money

      I know an Apple fan probably doesn't want to hear this, but a change that cripples third party monitors is no accident. I doubt Apple considers it broken or in need of a fix, it's actually likely the initial state was considered a bug or oversight. Creating incompatibility and then using it as a sales opportunity is kind of Apple's bread and butter. "What else do you expect from some lousy third party? Genuine Apple stuff just works, buy our monitors and you'll see how much better they are!"

      1. bazza Silver badge

        Entirely believable though that is, I'd estimate that even Apple would sense that there might be a class action heading their way, we're they to give off any hint of such a standpoint.

        Unless they fix it quickly, there may be one anyway.

  8. anthonyhegedus Silver badge

    I use my m1 MacBook pro with a 2K (2560 x 1440) 32" screen, so it's certainly big enough to run at full resolution; I can't say I ever tried to run it in scaled-up mode. That's a big omission from Apple, and one that they should address. Connecting to stuff and 'just working' is a thing Apple are (were?) known for. They need to fix that pretty soon. I'd be most pissed off if I had a 24" screen that I couldn't scale.

    1. Anonymous Coward
      Anonymous Coward

      I'm running a 43" LG at full res (3840 x 2160) off an M1 mini and it has no problems, but that wasn't the case initially. Initially I could only get it there via HDMI, not USB-C. That seems to have improved, but I am certainly going to test this code.

  9. DJV Silver badge

    "spokespeople were not available for comment"

    You surprise me!


  10. TReko

    Apple has already fixed the problem

    buy an Apple branded monitor for $6,000 and it will "just work"

    1. LovesTha

      Re: Apple has already fixed the problem

      Did you miss the bit where people with that monitor are also using it because they don't like the default scaling?

    2. I ain't Spartacus Gold badge

      Re: Apple has already fixed the problem

      Was this the monitor that requires the $500 stand as an extra?

      1. newyork10033

        Re: Apple has already fixed the problem

        I do believe that stand is $1000 (or $999), no?

  11. mtrantalainen

    The problem isn't M1 but broken displays

    The real problem is incorrect EDID data in way to many displays. The hardware is technically broken but instead of fixing the hardware the manufacturers of said displays add workarounds to display drives. And those workarounds are not compatible with M1 hardware. (Typical problem in the hardware is having EDID metadata define display dimensions with numeric values matching display dimensions in mm but the metadata declares units as cm instead which obviously results values being off by a magnitude! As a result the display looks to OS like big TV screen instead of HDPI monitor.)

    Linux users see all the same problems because manufacturers do not support Linux so end users need to create the workarounds from scratch. For some reason, Apple doesn't allow similar user defined overrides on M1 hardware.

    1. Anonymous Coward
      Anonymous Coward

      Re: The problem isn't M1 but broken displays

      Yes, but a well designed system should be able to cope with broken or incomplete hardware.

      That's why we have error correction. Try/catch/fail. Redundancy checks.

      Because things aren't perfect, and you have to for accommodate that. Apple's attitude is "We didn't design it so we don't care if it works or not" which is great, but only if you stay entirely within their ecosystem. Which is what they want.

    2. Smirnov

      Re: The problem isn't M1 but broken displays

      While some monitors might provide broken EDID information, that isn't the issue here as the same problem appears with monitors that certainly provide correct EDID information and which work fine with Windows, Linux and macOS on intel Macs.

      It's just M1 Macs where they don't work (which suggests that it's not the monitor which is at fault here).

    3. Anonymous Coward
      Anonymous Coward

      Re: The problem isn't M1 but broken displays

      Exactly. My monitor didn't report correct EDID codes, and that's where it all started..

    4. Anonymous Coward
      Anonymous Coward

      Re: The problem isn't M1 but broken displays

      I miss VGA....

  12. Henry Wertz 1 Gold badge

    Port EDID code

    Sounds like a matter of porting the EDID handling code -- I would guess it's probably written in C (... or maybe ObjectiveC or Swift?) and could just port over the x86 code to replace the current iOS-derived code.

  13. cb7

    "enourmously embarassing for Apple"

    To feel embarrassed, one has to give a shit. If they gave a shit, they would have fixed the issue already.

  14. easytoby
    Thumb Up

    SwitchResX has being doing this for a while

    The team at had an M1 update out early for SwitchResX which solved the external display issues for me, and also allowed M1 MacMini to address a big curved monitor (Philips Brilliance 499P) properly.

  15. arachnoid2

    Down votes

    Is the reg not going to go the way of YouTube and hide the down vote count (it would help Apple threads no end)?

    1. I ain't Spartacus Gold badge

      Re: Down votes

      The first rule of downvote club is not to talk about... Giant marshmallows?

  16. Dolvaran

    Shame no one can fix the 'no sound through DisplayPort ' on the recent MacOS versions.

    1. zuckzuckgo

      On DisplayPort, no one can hear you scream.

  17. boblongii

    Not 6K

    Vertical resolution is actually just a shade over 3K.

    Yes, I know the "industry" got together and agreed to double all the numbers to look better, but I don't remember else saying that they should be allowed to decide that sort of thing for themselves.

    In any case, the resolution is 218DPI, which is still less than 300, which is known in typesetting as "draft mode".

  18. Anal Leakage

    My M1 drives my QHD display just fine

    Another steaming pile of Reg Apple hate. See title

  19. rombout

    I wonder if these details about external monitors issues was stated in the footnotes on the product page. Thats quite disappointing to read it has such issues. Im quite baffled they released it actually like this

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