10.15.6, external display problem

Both screens are not displayed when connecting an external monitor after 10.15.6 upgrade.

Before the upgrade, it worked fine in version 10.15.5.


Is there any solution about this ?

MacBook Pro 16″, macOS 10.15

Posted on Jul 22, 2020 9:01 AM

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Question marked as Top-ranking reply

Posted on Jul 29, 2020 12:37 PM

You can't expect to get high resolutions from either of those displays when you connect them via Analog VGA. it is simply too weak and no one is testing it any more.


If you complain long enough and hard enough, you will force Apple to revise their specs to say they no longer support Analog VGA connection. they will NOT fix this.


Both of those displays support [Full Size] DisplayPort input. you should use a cable that also converts from the computer's USB-C port to the display's DisplayPort input, and your troubles will disappear.


Apple sells this one:

Moshi USB-C to DisplayPort Cable $49.95


MonoPrice sells this one:

Monoprice USB Type-C to DisplayPort 3.1 Cable - 5Gbps, Active, 4K@60Hz, Black, 6ft - Product # 24444 - $22.24


I am sure there are others as well.


If you prefer, you could connect using HDMI, a consumer-level interface, but getting the correct cables is more complex.



49 replies

Oct 13, 2020 5:00 PM in response to youngsinatra313

This is a User-to-User Support Community.


W hen you post that you have checked this against multiple different VGA displays, and all did not work, it leads me think that VGA displays are your preference for daily use, and that is what my reply was about.


If you "'don't see my comments helping to resolve this issue in any way", I invite you to use the Contact Support link at the top of any Forum web page and complain to an Apple employee rather than having a discussion with other Users who sometimes have insights into such issues.



Jul 31, 2020 2:15 PM in response to tafelzout

SUCCESS! (?)


Well, I broke down and purchased a USBc to VGA Belkin adapter and this monitor now works. For those struggling with this issue, this isn't a solution to the original problem, but it works. I bought it from the Apple Store for $32 dollars. Is it worth $32 dollars? I would say so if it gets my monitor up and running. Is it good that I needed to spend $32 to get a monitor working because of an OS update? No... but you may think otherwise.


Link to the product, which you can probably get at half the price elsewhere is below. (but I wanted Apple to own this if it didn't work so I bought it through them...)


https://www.apple.com/shop/product/HJUZ2ZM/A/belkin-usb-c-to-vga-adapter?afid=p238%7CsDb8WwLtF-dc_mtid_1870765e38482_pcrid_246387003261_pgrid_49565832687_&cid=aos-us-kwgo-pla-btb-3pp--slid---product-HJUZ2ZM/A



Jul 31, 2020 2:35 PM in response to sdailey123

It has been suggested that the graphics subsystem has always had the ability to test the integrity of cables used to connect displays. It is possible we are seeing Apple more-closely enforcing the correct standards.


There are three types of HDMI cables, but they are generally impossible to tell apart once they are out of the box;


Standard --

suitable for up to 1080i and 720p NB> this is nowhere near HD, which uses twice that data rate for 1080p


High speed --

suitable for 1080p, or 4K 2 30 Hz, not faster, and deep color at those rates


Premium high speed /Ultra High Speed --

REQUIRED for anything faster than 4K at 30Hz.


.


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10.15.6, external display problem

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