Hey everyone!
I just bought new monitor for my home office setup - NEC EA271U and have some serious issues with it when trying to use USB-C connection.
When it is plugged in it charges the computer just fine, displays screen for about 10s and turns black/no signal, while it is still visible in About this Mac - Displays section as well as in the preferences panel. Mac sees it as connected, I can drag apps there, etc, but the display is not showing anything. I dug through tens of threads regarding external displays problems but no solution.
Using Big Sur 11.1, but saw some posts such issues started appearing since Catalina release.
Things I tried:
- PRAM/NVRAM reset (command + option + P + R)
- three different cables - one I use with my other 4k usb-c monitor, that came with it (LG 27UL850), two 4k@60Hz 10Gbps, c-c cables with 100W PD capabilities
- tried two different Macs - MacBook Pro 16 and MacBook Air M1 - on the M1 it doesn't even show up for 10s
- IN SAFE MODE IT WORKS - but just up to 1920x1080p
- USB-C to HDMI adapter works fine, but its just 30Hz at 4K
I don't want to use any other connection but USB-C.
Anyone of you had similar issues? I literally spent half of the day looking for a solution. On some Polish forums users with same problems told me it must be some Mac OS fault because they are using Windows just fine with same setup.
Maybe some kexts are broken, maybe some PD negotiation going wrong.
Here is displaypolicyd log. maybe you can find some clue there:
Youtube video showing how it looks when connected:
I just bought new monitor for my home office setup - NEC EA271U and have some serious issues with it when trying to use USB-C connection.
When it is plugged in it charges the computer just fine, displays screen for about 10s and turns black/no signal, while it is still visible in About this Mac - Displays section as well as in the preferences panel. Mac sees it as connected, I can drag apps there, etc, but the display is not showing anything. I dug through tens of threads regarding external displays problems but no solution.
Using Big Sur 11.1, but saw some posts such issues started appearing since Catalina release.
Things I tried:
- PRAM/NVRAM reset (command + option + P + R)
- three different cables - one I use with my other 4k usb-c monitor, that came with it (LG 27UL850), two 4k@60Hz 10Gbps, c-c cables with 100W PD capabilities
- tried two different Macs - MacBook Pro 16 and MacBook Air M1 - on the M1 it doesn't even show up for 10s
- IN SAFE MODE IT WORKS - but just up to 1920x1080p
- USB-C to HDMI adapter works fine, but its just 30Hz at 4K
I don't want to use any other connection but USB-C.
Anyone of you had similar issues? I literally spent half of the day looking for a solution. On some Polish forums users with same problems told me it must be some Mac OS fault because they are using Windows just fine with same setup.
Maybe some kexts are broken, maybe some PD negotiation going wrong.
Here is displaypolicyd log. maybe you can find some clue there:
Code:
2020-12-03 16:05:39.480472+0100: NOTICE: kIOFBNotifyOnlineChange 0x1 fb[ 1 ] -> online, Thu Dec 3 16:05:39 2020
2020-12-03 16:05:39.480541+0100: NOTICE: Update display map to fb[ 1 ] - online
2020-12-03 16:12:45.182066+0100: LinkUpdate: 3.0 event: Remove [1]
2020-12-03 16:12:45.182220+0100: NOTICE: Addr: 3.0 event: Remove [1] source: 0
2020-12-03 16:12:45.182296+0100: NOTICE: Do offline device addr 3.0 flags 0x0
2020-12-03 16:12:45.182348+0100: NOTICE: FB AGDC state FB[1] - OFF
2020-12-03 16:12:45.182624+0100: NOTICE: inject FB[1] change
2020-12-03 16:12:45.464243+0100: NOTICE: kIOFBNotifyOnlineChange 0x3 fb[ 1 ] -> offline, Thu Dec 3 16:12:45 2020
2020-12-03 16:12:45.464315+0100: NOTICE: Update display map to fb[ 1 ] - offline
2020-12-03 16:12:45.464331+0100: NOTICE: Release fb[ 1 ] resources
2020-12-03 16:12:45.464360+0100: NOTICE: Do LT off on port 3
2020-12-03 16:12:45.464574+0100: NOTICE: Port[3] - DP link down
2020-12-03 16:12:52.202259+0100: NOTICE: accepted No_Media_Mode enter, Thu Dec 3 16:12:52 2020
2020-12-03 16:12:52.632042+0100: NOTICE: kIOFBNotifyOnlineChange 0x1 fb[ 0 ] -> offline, Thu Dec 3 16:12:52 2020
2020-12-03 16:12:52.632097+0100: NOTICE: Update display map to fb[ 0 ] - offline
2020-12-03 16:12:52.732468+0100: NOTICE: accepted No_Media_Mode exit, Thu Dec 3 16:12:52 2020
2020-12-03 16:12:52.732607+0100: NOTICE: accepted No_Media_Mode enter, Thu Dec 3 16:12:52 2020
2020-12-03 16:12:53.694129+0100: NOTICE: accepted No_Media_Mode exit, Thu Dec 3 16:12:53 2020
2020-12-03 16:12:54.785965+0100: LinkUpdate: 3.0 event: Remove [1]
2020-12-03 16:12:54.786073+0100: NOTICE: Addr: 3.0 event: Remove [1] source: 0
2020-12-03 16:12:54.950275+0100: NOTICE: accepted No_Media_Mode enter, Thu Dec 3 16:12:54 2020
2020-12-03 16:12:54.951212+0100: NOTICE: kIOFBNotifyOnlineChange 0x0 fb[ 0 ] -> online, Thu Dec 3 16:12:54 2020
2020-12-03 16:12:54.951236+0100: NOTICE: Update display map to fb[ 0 ] - online
2020-12-03 16:12:55.797035+0100: LinkUpdate: 3.0 event: Change [2]
2020-12-03 16:12:55.797099+0100: NOTICE: accepted No_Media_Mode exit, Thu Dec 3 16:12:55 2020
2020-12-03 16:12:55.797219+0100: NOTICE: doChange: addr 1.0 [7]
2020-12-03 16:12:55.797287+0100: NOTICE: doChange: addr 2.0 [7]
2020-12-03 16:12:55.797585+0100: NOTICE: doChange: addr 3.0 [7]
2020-12-03 16:12:55.992184+0100: NOTICE: Populated addr 3.0 38a3:2dda UUID 0 order 0:0 tx 2:2 dsp 1 WL 0 MS 0 edid 256 undef 0 DSC 0
2020-12-03 16:12:55.992334+0100: NOTICE: doChange: addr 4.0 [7]
2020-12-03 16:12:55.992439+0100: NOTICE: doChange: addr 5.0 [7]
2020-12-03 16:12:56.214812+0100: NOTICE: Do online device addr 3.0 processCount 1
2020-12-03 16:12:56.216199+0100: NOTICE: Sync LinkTrain Port: 3: SST, 4 lanes @ HBR2 FEC disabled
2020-12-03 16:12:56.296921+0100: NOTICE: FB AGDC state FB[1] - ON
2020-12-03 16:12:56.296981+0100: NOTICE: inject FB[1] change
2020-12-03 16:12:56.297014+0100: NOTICE: Do online device addr 3.0 id 38a3:2dda UUID 0 order 0:0 edid 256 undef 0 - completed
2020-12-03 16:12:56.297054+0100: NOTICE: Addr: 3.0 event: Change [2] source: 3
2020-12-03 16:12:56.297072+0100: NOTICE: doChange: addr 3.0 [3]
2020-12-03 16:12:57.387406+0100: NOTICE: kIOFBNotifyOnlineChange 0x1 fb[ 1 ] -> online, Thu Dec 3 16:12:57 2020
2020-12-03 16:12:57.387458+0100: NOTICE: Update display map to fb[ 1 ] - online
2020-12-03 16:12:57.388980+0100: NOTICE: Port non-scanned FB[ 1 ] link is good ...
2020-12-03 16:12:57.591740+0100: NOTICE: Populated addr 3.0 38a3:2dda UUID 0 order 0:0 tx 2:2 dsp 1 WL 0 MS 0 edid 256 undef 0 DSC 0
2020-12-03 16:12:57.591769+0100: NOTICE: Device addr 3.0 is same ...
2020-12-03 16:12:57.591834+0100: NOTICE: Addr: 3.0 event: Change [2] source: 0
2020-12-03 16:12:57.591848+0100: NOTICE: doChange: addr 3.0 [0]
2020-12-03 16:12:57.593274+0100: NOTICE: Port non-scanned FB[ 1 ] link is good ...
2020-12-03 16:12:57.842227+0100: NOTICE: Populated addr 3.0 38a3:2dda UUID 0 order 0:0 tx 2:2 dsp 1 WL 0 MS 0 edid 256 undef 0 DSC 0
2020-12-03 16:12:57.842266+0100: NOTICE: Device addr 3.0 is same ...
2020-12-03 16:12:57.842333+0100: NOTICE: doChange: addr 1.0 [7]
2020-12-03 16:12:57.842349+0100: NOTICE: doChange: addr 2.0 [7]
2020-12-03 16:12:57.842384+0100: NOTICE: doChange: addr 3.0 [7]
2020-12-03 16:12:57.843812+0100: NOTICE: Port non-scanned FB[ 1 ] link is good ...
2020-12-03 16:12:58.091877+0100: NOTICE: Populated addr 3.0 38a3:2dda UUID 0 order 0:0 tx 2:2 dsp 1 WL 0 MS 0 edid 256 undef 0 DSC 0
2020-12-03 16:12:58.091913+0100: NOTICE: Device addr 3.0 is same ...
2020-12-03 16:12:58.091975+0100: NOTICE: doChange: addr 4.0 [7]
2020-12-03 16:12:58.092016+0100: NOTICE: doChange: addr 5.0 [7]
Youtube video showing how it looks when connected:
Last edited: