Urgent: External Display Not Detected on New MacBook Pro 16" M2 - Need Advanced Technical Support

cloudsurf-digital wrote:

Dear Apple Community and Technical Experts,

I recently upgraded from a MacBook Pro 16" M1 (2021) to a 2023 MacBook Pro 16" M2 (2023). While my previous setup worked seamlessly with a Samsung Odyssey C49G94TSSP Ultrawide 49" 120Hz display via DisplayPort to USB-C cable, the new M2 machine fails to detect this external screen. And "fails to detect" means, there's no indicator that a device has been connected at all.

I could be mistaken, but it looks like this monitor has a resolution of 5120x1440 pixels – the equivalent of two 27" 2560x1440 monitors set side-by-side.

Some random thoughts:

Macs have sometimes had problems with selecting the correct resolution for ultra-wide monitors, even when those monitors have trimmed-down resolution. E.g., a Mac might easily drive a 3840x2160 ("4K") monitor – and yet have problems driving a 3840x1080 ("ultra-wide") monitor with only half of the pixel count.

This monitor has somewhat fewer pixels than a 3840x2160 monitor would. So driving it may theoretically be within the capabilities of USB-C (DisplayPort) (as opposed to the higher-bandwidth Thunderbolt). It looks like the monitor itself has HDMI and DisplayPort inputs (no USB-C, no Thunderbolt), so then the questions arise as to whether

• The USB-C (DisplayPort) output on the Mac can support 5120x1440 resolution
• The USB-C (DisplayPort) to {DisplayPort, HDMI} adapter that you are using can support that resolution

Both the computer and the adapter would need to support the resolution, and 5120x1440 is unusual enough that adapter advertising doesn't tell you anything about whether you can expect support for that resolution.

This Apple Community thread may be of interest:

Why 5120x1440 Doesn't Work with Apple M1 - Apple Community

Someone reported that they had a 5120x1440 pixel Samsung 49" CRG9 – and that to get 5120x1440, they had to order a cable that supported DisplayPort 1.4, change the refresh rate setting on the monitor from 120 Hz to 60 Hz, and turn off Freesync. After that, they still had problems with the system not detecting the monitor when waking from sleep. But maybe that thread will give you a lead on how to get your setup working …

The Mac uses a system that reminds me of “Plug and play” to determine what display is connected, and what its capabilities are.

To get a Mac display to become active, you need the Mac to query the display, and the display to answer with its name and capabilities. Otherwise, the display will not be shown as present, and no data will be sent to the display. "No signal detected" is generated by the DISPLAY, not by the Mac.

This query is only sent at certain times:

• at startup

• at wake from sleep — so momentarily sleeping and waking your Mac may work

• at insertion of the Mac-end of the display-cable, provided everything on that cable is ready-to-go

• hold the Option key while you click on the (Detect Display) button that will appear in Displays preferences (from another display)

so try doing some of those things and see if the display comes alive.

I recommend contacting the display's support team for assistance. It is their product and they will know best how to address this problem. Good luck

No, the suggestion is to contact Samsung.

Apple is not the device manufacturer.

If Samsung is telling you to talk to the device manufacturer, Samsung is telling you to talk to Samsung.

On the link you provide, the phrase "device manufacturer" is not found. Neither is "refers" or "works under any circumstances"

You are misreading something. Samsung is responsible for making their products work with macOS, not the other way around.

But, good luck moving forward.

ku4hx wrote:

Apple is not the device manufacturer.

https://www.samsung.com/us/support/troubleshooting/TSG01110761/#check-for-updates-for-the-monitor

"Contact the manufacturer of the PC or device, if needed.

If the monitor works at any point, then the monitor does not need service. Examples of when it might work even if it doesn't work in normal mode:

• • When booting before the operating system loads
  • In Safe Mode
  • When used as a second monitor
  • When used with a different device

If the monitor works in any of these situations, but updates do not resolve the issue for normal mode, or there are no updates available, then contact the manufacturer of the PC or device that the monitor doesn't work with. If it's a custom built PC, contact the manufacturer of the graphics card or motherboard that the monitor is plugged into."

If Samsung is telling you to talk to the device manufacturer, Samsung is telling you to talk to Samsung.

They're telling their customers to talk to the computer manufacturer – in this case, Apple.

Samsung is responsible for making their products work with macOS, not the other way around.

Samsung's position is obviously that computer manufacturers are responsible for making their computers work with Samsung displays, not the other way around.

cloudsurf-digital wrote:

Device Testing•

• M2's right-side USB-C port works with the display

• Left-side USB-C ports on M2 don't detect the display, but work with other devices

• Purchased another M2 (it's gonna get really expensice now :-(), I had high hopes but even worse - no USB-C ports detect the screen, not even the right-side port

That's really strange. Assuming that you used the same adapter to conduct all of the tests, I would expect all the tests to have the same result!

Hi,

I'm experiencing same issue. I have MacBook 14 inc 2023 Sonoma 14.1. While I connect Monitor directly to MacBook via HDMI I will not face any error however once I connect same Monitor (Samsung Odyssa ultra wide) via Displayport to Docking station HP and USB C to MacBook then Macbook not detect the Monitor but the Docking Station is connecting and even connected bluetooth mouse working.