Weird iMac Retina 5K e-gpu resolution problems. HELP!!!

[denstorefedepikkemand456]

I’ve been trying to get a GTX980Ti working on an iMac Retina 5K running El Capitan 10.11.3, latest version of CUDA, using a Sonnet PCIe expander over Thunderbolt and the automate-eGPU script found here:

https://github.com/goalque/automate-eGPU

Unfortunately I’ve only have had mixed success to getting it to work - the external card will get recognized by the OS and the Cuda compatible software, but the iMacs display will run in a square 1:1 mode (see images attached) having black borders on both sides, making it’s pretty much useless.
As soon as the automate-eGPU script is uninstalled (and the external graphics card becomes unavailable) the iMac’s display is back to normal again.

I don't need to run the GFX card as the primary screen card. I just need Cuda to detect it as a secondary card.

I’m willing to pay someone X euros to help me resolve this - I already spent many hours trying to troubleshoot and figuring out why this is happening. I’ve also tried with other graphicscards (earlier GTX models) and the result is the same. Any ideas?

[netkas]

make backup of kext AppleGraphicsControl.kext before running that script, then run the script, then restore that kext from backup.

This will give you cuda but no output from 980ti.

if that works, you can donate me via link on http://netkas.org

basically what that scripts modifies in AppleGraphicsDevicePolicy.kext (which is inside of AppeGraphicsControl.kext) is not good for retina imac, it breaks OSX ability to use MST screen on 5k imac, so you getting only half of screen output.

The author of that script isn't very smart.

[denstorefedepikkemand456]

Sickest shit man! Thank you so much! its working perfectly! I'll transfer some dough straight away!!!!!! THANK YOU!!!!

[Zodi]

Hi,

i've a question about your configuration!
You have an iMac connected to an eGPU System with a graphic card and this card is connected back to the iMac???

Thx Zodi

[Pixelreality]

make backup of kext AppleGraphicsControl.kext before running that script, then run the script, then restore that kext from backup.

This will give you cuda but no output from 980ti.

if that works, you can donate me via link on http://netkas.org

basically what that scripts modifies in AppleGraphicsDevicePolicy.kext (which is inside of AppeGraphicsControl.kext) is not good for retina imac, it breaks OSX ability to use MST screen on 5k imac, so you getting only half of screen output.

The author of that script isn't very smart.

I have the same issue, and tried to backup the kext file and then restore it after running the automate egpu script. But it breaks my Mac completely so it won't boot. It just gets stuck during boot :-(.
If I boot in recovery mode and reinstall OS X on top of the old systems it works again, until I reinstall the egpu.

Anyone have a solution?

[Rominator]

With a 4K or 5K iMac if you want to use external display, you either need an EFI eGPU (not released yet) or you run Goalie's script and accept that the internal screen gets messed up.

If you don't let it modify the AGDC extension, you will retain internal screen and be able to use cuda but no external display via eGPU.

Keep a virgin AGDC and replace it using official kext drop type app.

[yrelyk]

make backup of kext AppleGraphicsControl.kext before running that script, then run the script, then restore that kext from backup.

This will give you cuda but no output from 980ti.

if that works, you can donate me via link on http://netkas.org

basically what that scripts modifies in AppleGraphicsDevicePolicy.kext (which is inside of AppeGraphicsControl.kext) is not good for retina imac, it breaks OSX ability to use MST screen on 5k imac, so you getting only half of screen output.

The author of that script isn't very smart.

I recently built an eGPU with a GTX 980, and connected to a 5k iMac. After trying instructions on MacRumors on how to get it working in OS X,  and those software hacks did not get it working (non-EFI) I stumbled upon this forum and the automatic-eGPU script. I ran the script and after a reboot my 5k had the same problem as of OP...I uninstalled the script, backed up the kext, and ran the script again. After rebooting the 5k was still showing a small square picture, while my Dell Ultrasharp 1440p fully worked connected to the 980. When I started to replace the kext that I backed up both screens turned off. I softly pressed the power button and it immediately turned back on (it likely went to sleep even though I have that disabled), only this time the 5k was back to normal (3200x1800). so it seems to me that the script was improved recently.

Now if only I can get it to work in Windows...I tried this first and the drivers seem to have been clashing (nVidia and AMD). The picture was mirrored to both displays even though they were using different video cards. I fiddled with the very limited settings for a while and the 5k turned off. I went to reboot and got a sad face . So now I can only boot into Windows with eGPU unplugged.

[yrelyk]

Hi,

i've a question about your configuration!
You have an iMac connected to an eGPU System with a graphic card and this card is connected back to the iMac???

Thx Zodi

The short answer is no, although if you have a mac with integrated graphics you can install nVidia Optimus (For Windows only) and get the features you asked for in Windows. However you can still use the CUDA cores for advanced graphic design without the need for an external monitor in OS X. Just don't expect to play games on your macs monitor accelerated by the eGPU.

[Caden]

Hi,

i've a question about your configuration!
You have an iMac connected to an eGPU System with a graphic card and this card is connected back to the iMac???

Thx Zodi

The short answer is no, although if you have this a mac with integrated graphics you can install nVidia Optimus (For Windows only) and get the features you asked for in Windows. However you can still use the CUDA cores for advanced graphic design without the need for an external monitor in OS X. Just don't expect to play games on your macs monitor accelerated by the eGPU.

That makes sense. I tried the instructions on the Mac Rumors site as well with no luck.

[Rominator]

With 5K iMac you can either have external screen work well on eGPU or have internal screen work well and use CUDA/OpenCl on eGPU.

[fminus]

With 5K iMac you can either have external screen work well on eGPU or have internal screen work well and use CUDA/OpenCl on eGPU.

Is this still the current status for an egpu on the imac?
I would like to use a RX480/Nano on a imac 5k and only use it to push the internal screen.