I have an external screen at work, which my MacBook used to recognize without issue. When I came today and plugged it in, it didn't recognize it anymore. It is connected via a Displayport-to-DVI adapter, to a HP ZR2440w display.
I followed all the steps in the standard apple support thread on this topic, including reseting PRAM using Option+Command+p+r. I also updated from OS X 10.9 to 10.10 hoping that may help.
Here's some specs:
- MacBook Pro (Retina, 15-inch, Late 2013).
- Processor: 2.6 GHz Intel Core i7
- Memory: 16 GB 1600 MHz DDR3
- Graphics: Intel Iris Pro 1536 MB
Following the answer Late 2011 13" MacBook Pro doesn't detect external monitor anymore on Mavericks, I also had a look at Color Sync, under Devices, Displays. There is only Color LCD. It lists the same profile under Factory profile and current profile.
When I plug in the cable, it does respond though: It stops using the onboard graphics and uses the Nvidia instead. But that's all I can detect.
How can I proceed?
Update: gfxCardStatus
As per the other answer, I downloaded gfxCardStatus and set it to discrete graphics only. Then, it was working for a day. Today, it again didn't work. Here's some log activity for yesterday, when it was working. I hope that's sufficient, I dont understand enough of this, but there is some Thunderbolt action going on:
8/19/15 3:03:09.000 PM kernel[0]: Wake reason: RTC (Alarm)
8/19/15 3:13:20.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:13:20.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/19/15 3:13:20.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 2 us
8/19/15 3:13:20.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 134 milliseconds
8/19/15 3:13:20.000 PM kernel[0]: ARPT: 51933.872603: AirPort_Brcm43xx::powerChange: System Wake - Full Wake/ Dark Wake / Maintenance wake
8/19/15 3:13:20.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:13:20.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/19/15 3:13:25.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/19/15 3:13:25.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/19/15 3:14:06.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:14:07.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 1 us
8/19/15 3:14:07.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 0 milliseconds
8/19/15 3:14:08.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:14:09.000 PM kernel[0]: Wake reason: RTC (Alarm)
8/19/15 3:26:56.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:26:56.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/19/15 3:26:56.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 1 us
8/19/15 3:26:56.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 132 milliseconds
8/19/15 3:26:56.000 PM kernel[0]: ARPT: 51983.227198: AirPort_Brcm43xx::powerChange: System Wake - Full Wake/ Dark Wake / Maintenance wake
8/19/15 3:26:56.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:26:56.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/19/15 3:27:01.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/19/15 3:27:01.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/19/15 3:27:42.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:27:43.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 28 us
8/19/15 3:27:43.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 0 milliseconds
8/19/15 3:27:44.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:27:45.000 PM kernel[0]: Wake reason: RTC (Alarm)
8/19/15 3:40:32.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:40:32.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/19/15 3:40:32.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 1 us
8/19/15 3:40:32.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 133 milliseconds
8/19/15 3:40:32.000 PM kernel[0]: ARPT: 52032.461467: AirPort_Brcm43xx::powerChange: System Wake - Full Wake/ Dark Wake / Maintenance wake
8/19/15 3:40:32.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:40:32.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/19/15 3:40:37.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/19/15 3:40:37.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/19/15 3:41:25.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:41:25.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 1 us
8/19/15 3:41:25.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 0 milliseconds
8/19/15 3:41:27.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:41:39.000 PM kernel[0]: Wake reason: XHC1
8/19/15 3:41:39.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:41:39.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/19/15 3:41:39.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 1 us
8/19/15 3:41:39.000 PM kernel[0]: The USB device Apple Internal Keyboard / Trackpad (Port 12 of Hub at 0x14000000) may have caused a wake by issuing a remote wakeup (2)
8/19/15 3:41:39.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000320
8/19/15 3:41:39.000 PM kernel[0]: full wake promotion (reason 1) 3 ms
8/19/15 3:41:39.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 1 milliseconds
8/19/15 3:41:40.000 PM kernel[0]: ARPT: 52088.903688: AirPort_Brcm43xx::powerChange: System Wake - Full Wake/ Dark Wake / Maintenance wake
8/19/15 3:41:40.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/19/15 3:41:40.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/19/15 3:41:40.504 PM WindowServer[2858]: CGXDisplayDidWakeNotification [52088906774120]: posting kCGSDisplayDidWake
8/19/15 3:41:40.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000300
8/19/15 3:41:40.985 PM sharingd[2913]: 15:41:40.985 : Starting AirDrop server for user 501 on wake
8/19/15 3:41:44.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/19/15 3:41:45.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
And here is some log from today, when it is not working. I slept the Macbook, opened the lid, plugged in the cable in and out of both display port slots.
8/20/15 12:46:56.627 PM WindowServer[2858]: CGXDisplayDidWakeNotification [90478887688873]: posting kCGSDisplayDidWake
8/20/15 12:51:38.000 PM kernel[0]: process com.apple.WebKit[6847] caught causing excessive wakeups. Observed wakeups rate (per sec): 163; Maximum permitted wakeups rate (per sec): 150; Observation period: 300 seconds; Task lifetime number of wakeups: 45932
8/20/15 12:51:38.495 PM ReportCrash[6878]: Invoking spindump for pid=6847 wakeups_rate=163 duration=277 because of excessive wakeups
8/20/15 12:51:40.130 PM spindump[637]: Saved wakeups_resource.diag report for com.apple.WebKit.WebContent version 10600 (10600.8.9) to /Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2015-08-20-125140_Samans-MacBook-Pro.wakeups_resource.diag
8/20/15 12:52:44.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 12:52:45.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 12:52:48.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 12:52:48.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 12:52:48.919 PM sharingd[2913]: 12:52:48.918 : Starting AirDrop server for user 501 on wake
8/20/15 12:52:49.015 PM WindowServer[2858]: CGXDisplayDidWakeNotification [90831286761992]: posting kCGSDisplayDidWake
Final set of logs: In the evening, after waking up, it worked again for a few minutes - but then, plugging it out and in, and it stopped working. Here is the session where first it worked, and then it stopped:
8/20/15 4:22:32.000 PM kernel[0]: Wake reason: RTC (Alarm)
8/20/15 4:22:32.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 4:22:32.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/20/15 4:22:32.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 1 us
8/20/15 4:22:32.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 132 milliseconds
8/20/15 4:22:32.000 PM kernel[0]: ARPT: 100129.865027: AirPort_Brcm43xx::powerChange: System Wake - Full Wake/ Dark Wake / Maintenance wake
8/20/15 4:22:32.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 4:22:32.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/20/15 4:22:37.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/20/15 4:22:37.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/20/15 4:23:18.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 4:23:19.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 1 us
8/20/15 4:23:19.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 0 milliseconds
8/20/15 4:23:20.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 4:23:21.000 PM kernel[0]: Wake reason: XHC1
8/20/15 4:31:44.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 4:31:44.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/20/15 4:31:44.000 PM kernel[0]: AppleThunderboltNHIType2::prePCIWake - power up complete - took 1 us
8/20/15 4:31:44.000 PM kernel[0]: The USB device Apple Internal Keyboard / Trackpad (Port 12 of Hub at 0x14000000) may have caused a wake by issuing a remote wakeup (2)
8/20/15 4:31:44.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000320
8/20/15 4:31:44.000 PM kernel[0]: full wake promotion (reason 1) 5 ms
8/20/15 4:31:44.000 PM kernel[0]: AppleThunderboltGenericHAL::earlyWake - complete - took 134 milliseconds
8/20/15 4:31:44.000 PM kernel[0]: ARPT: 100179.020287: AirPort_Brcm43xx::powerChange: System Wake - Full Wake/ Dark Wake / Maintenance wake
8/20/15 4:31:44.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
8/20/15 4:31:44.000 PM kernel[0]: AppleCamIn::wakeEventHandlerThread
8/20/15 4:31:44.000 PM kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000300
8/20/15 4:31:44.757 PM sharingd[2913]: 16:31:44.756 : Starting AirDrop server for user 501 on wake
8/20/15 4:31:44.955 PM WindowServer[2858]: CGXDisplayDidWakeNotification [100179246905649]: posting kCGSDisplayDidWake
8/20/15 4:31:49.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
8/20/15 4:31:49.000 PM kernel[0]: AppleCamIn::handleWakeEvent_gated
