Intel Hd 4000 graphics on imac 13,2

[jb40]

Hi,
I have an Imac 13,2 ( 27'' i5 2,9 GHZ Model A1419 (emc 2546) graphics GeForce GTX 660M )
i have a prob with the display (27") i think it's a NVIDIA GeForce GTX 660M problem.
So PLZ how to enable the intel HD 4000 graphics on the CPU in this model and disable the nvidea.
Thank you

 

[Edhawk]

Try the following:

1. Create an OpenCore Legacy Patcher (OCLP) USB to boot your iMac13,2. You don't need any Post Install Root Patches, as you are running a supported version of macOS.
   • https://dortania.github.io/OpenCore-Legacy-Patcher/
2. In the OCLP config.plist add framebuffer entries for your Intel HD4000 IGPU.
   • 
   • The framebuffer entry is required to allow the HD4000 to drive the display.
3. In the config.plist add -wegnoegpu boot argument, to disable your discrete Nvidia graphics card.
4. Boot your iMac from the OCLP USB.

The above assumes you will take the time to read the OCLP guide and follow the instructions correctly. You would be surprised how often that is not the case.

Alternative cause for display issues:
Although you think the issue is caused by the Nvidia dGPU, that may not be the case.

Issues like this are just as likely to be caused by a defective display, defective video screen connector cable, damaged LDVS connector or a defective LED Backlight Inverter Board. I have had all of these issues with iMacs I have owned. Finding out which was the cause wasn't straight forward nor was it cheap.

To test to see if the LED Backlight Inverter board is defective, do the following:

• Turn on your iMac.
• Place the flat of your hand on the rear top left hand side of the iMac case, does it feel hot, not warm, but overly hot.
• If that is the case then your LED Backlight Inverter Board is probably on its way out and will need replacing.

 

[jb40]

Try the following:

1. Create an OpenCore Legacy Patcher (OCLP) USB to boot your iMac13,2. You don't need any Post Install Root Patches, as you are running a supported version of macOS.
   • https://dortania.github.io/OpenCore-Legacy-Patcher/
2. In the OCLP config.plist add framebuffer entries for your Intel HD4000 IGPU.
   • View attachment 574192
   • The framebuffer entry is required to allow the HD4000 to drive the display.
3. In the config.plist add -wegnoegpu boot argument, to disable your discrete Nvidia graphics card.
4. Boot your iMac from the OCLP USB.

The above assumes you will take the time to read the OCLP guide and follow the instructions correctly. You would be surprised how often that is not the case.

Alternative cause for display issues:
Although you think the issue is caused by the Nvidia dGPU, that may not be the case.

Issues like this are just as likely to be caused by a defective display, defective video screen connector cable, damaged LDVS connector or a defective LED Backlight Inverter Board. I have had all of these issues with iMacs I have owned. Finding out which was the cause wasn't straight forward nor was it cheap.

To test to see if the LED Backlight Inverter board is defective, do the following:

• Turn on your iMac.
• Place the flat of your hand on the rear top left hand side of the iMac case, does it feel hot, not warm, but overly hot.
• If that is the case then your LED Backlight Inverter Board is probably on its way out and will need replacing.

Thank you ED,
I thing you are right maybe it's the LED Backlight inverter board problem, the display is very hot i will send pic. i will try to try solutions step by step first by enabling the discrete Intel HD 4000 graphics and make off the NVIDIA graphic card.