Hello guys
I plug a 2nd screen (Philips) on my iMac late 2013 (with GTX 780M 4G°) by Minidisplay to HDMI.
It works fine... but, sometimes, when i reboot or start a new session, the display stay off and doesn't appear in the display preferences.
I change the cable, i unplugged and replugged... nothing. Only a reboot (sometimes) or a "Cmd Alt PR" solve the problem.
It worked fine with my late 2009 imac... Any idea ?
iMac, OS X Mavericks (10.9.2)
Hello there, Zeustef.
The following Knowledge Base article provides some great recommendations for troubleshooting issues with display:
Apple computers: Troubleshooting issues with video on internal or external displays
http://support.apple.com/kb/ht1573
No video or no signal, image distortion, "snow," or flickering
Check connections
When using an external display be sure to check the following:
- If you're using an Apple notebook, confirm the AC power cable or adapter is securely connected to the computer and the cable providing power to the display is also secure. It is always good to have your notebook connected to AC power when an external display is in use.
- Confirm display adapters are fully seated in their respective connections and that they are supported models and for the computer and display. Refer to these articles to assist you with adapter compatibility and further configuration information:
- Remove all display cable extenders, KVM switches, or other like devices and retest to determine if the issue is resolved.
- Try unplugging the video adapter or cable and then plug it back in.
- If more than one video adapter is in use (or "daisy-chained"), troubleshoot by using only one adapter.
Example: A mini DisplayPort to DVI adapter connected to a DVI to HDMI adapter is an unsupported configuration because there is a series of adapters in use.
- If available, try using a different display and or adapter (or use a different connector by using DVI instead of VGA, for instance).
Reset the system
You can reset the Mac's parameter RAM and SMC.Reset the resolutionStart by resetting the Mac's parameter RAM. If the display does not come up, was previously set to an unsupported resolution, and still results in no video:
- Start up in Safe Mode.
- From the Apple () menu, choose System Preferences.
- Choose Displaysfrom the View menu to open the preferences pane.
- Select any resolution and refresh rate that your display supports.
- Restart your computer.
Thanks for reaching out to Apple Support Communities.
Cheers,
Pedro.
Hello there, Zeustef.
The following Knowledge Base article provides some great recommendations for troubleshooting issues with display:
Apple computers: Troubleshooting issues with video on internal or external displays
http://support.apple.com/kb/ht1573
No video or no signal, image distortion, "snow," or flickering
Check connections
When using an external display be sure to check the following:
- If you're using an Apple notebook, confirm the AC power cable or adapter is securely connected to the computer and the cable providing power to the display is also secure. It is always good to have your notebook connected to AC power when an external display is in use.
- Confirm display adapters are fully seated in their respective connections and that they are supported models and for the computer and display. Refer to these articles to assist you with adapter compatibility and further configuration information:
- Remove all display cable extenders, KVM switches, or other like devices and retest to determine if the issue is resolved.
- Try unplugging the video adapter or cable and then plug it back in.
- If more than one video adapter is in use (or "daisy-chained"), troubleshoot by using only one adapter.
Example: A mini DisplayPort to DVI adapter connected to a DVI to HDMI adapter is an unsupported configuration because there is a series of adapters in use.
- If available, try using a different display and or adapter (or use a different connector by using DVI instead of VGA, for instance).
Reset the system
You can reset the Mac's parameter RAM and SMC.Reset the resolutionStart by resetting the Mac's parameter RAM. If the display does not come up, was previously set to an unsupported resolution, and still results in no video:
- Start up in Safe Mode.
- From the Apple () menu, choose System Preferences.
- Choose Displaysfrom the View menu to open the preferences pane.
- Select any resolution and refresh rate that your display supports.
- Restart your computer.
Thanks for reaching out to Apple Support Communities.
Cheers,
Pedro.
Hello. Thanks for your answer
Nope... it doesn't works...
I've tried all the issues (PRAM, SMC, changing cable, safe mode, ...) The result is the same. The second display is off when the iMac "sleeps" and i can'i turn it on before a reboot. Am i the only guy who want to have a seconde display with a HDMI plug in the world ???
I am very upset about Apple because this configuration worked without problem when i had a late 2009 iMac. I am sure the problem come from the video card (Nvidia GTX 780M) I'm very disapointed
Second display turned off
