I'm running OS12.6.3 Monterey. My external monitor was working perfectly with the laptop, until it stopped.
I made no changes to any settings on the macbook.
I restarted both.
I disconnected all other exterenal devices.
Any other suggestions?
[Re-Titled by Moderator]
MacBook Pro 15″, macOS 12.6
The Mac does not rely on Windows-like side-loaded "Drivers" which are actually packages of resolutions and settings for a specific display. Instead, it goes straight to the immutable source -- it asks the display itself.
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)
It's a 2017 Macbook Pro.
Monitor is Samsung ViewFinity UR50 28" 16:9 4K HDR FreeSync IPS Monitor
I'm connecting it with a type C to HDMI cable.
Please be aware - this was working just fine until recently. I made no changes to the laptop.
that Samsung ViewFinity UR50 28" appear to be
a 4K display with 10 bits/color HDR
interfaces include:
2x HDMI 2.0
1x DisplayPort 1.2
to support that display on one USB-C cable out of the Mac, you might be able to reach 50 Hz, or if you compromised color fidelity 60 Hz. that is a FAR from ideal connection. Any HDMI adapter from USB-C will get quite HOT and is likely to fail unexpectedly.
You would get slightly better colors and similar results but possibly better reliability of you connected with a DisplayPort adapter/cable. Be sure to keep that cable length under one meter.
The other issue sometimes seen is that when an error occurs in transmission, more recent versions of MacOS shut off the display. Too long cable are often the cause of those issues.
Higher refresh rates could be obtained with a ThunderBolt dock, or with two cables.
Oh, and I also tried different ports on my laptop.
what model-year MacBook Pro?
what make&model display?
how are you attempting to connect (what cables, adapters, and docks)?
Unable to connect my MacBook Pro running macOS Monterey with external monitor
