eGPU+External monitor, how to connect?

[JayMBP]

So I've been playing with the idea of going eGPU for my gaming/editing need while using external monitors and I hope if any MacRumor users is running this setup already can cast some light for me.

At first I thought the connection is MBP-TB3->Atikio Node-DP on GPU->Monitor. And that's fine for a regular monitor. But for my LG 5K, it would actually be MBP-TB3->Atikio Node on one side and MBP-TB3->LG 5K on the other since there's no TB3 equipped GPU out there.

Is my assumption correct and this would work? or should I be looking at a different monitor?

 

[theitsage]

It's possible to force/trick the eGPU to accelerate games/apps on the LG 5K. However, it's a lot of work and comes with additional performance loss. I'd recommend going with a different 5K monitor.

 

[JayMBP]

It's possible to force/trick the eGPU to accelerate games/apps on the LG 5K. However, it's a lot of work and comes with additional performance loss. I'd recommend going with a different 5K monitor.

Thanks for the comment.

Could you elaborate on the performance loss and procedure to achieve this? The way I thought is that if eGPU was capable of powering MBP's internal display, it should power the 5k over the other TB3 channel.

Ideally, I'd feature multi-display setup, a LG5k plus a LG 4k (31MU97). So, I could potentially use different monitor for different tasks, but they would be plugged in at all times when on desk.

 

[theitsage]

I wrote this overview of this process in a recent thread: The key is to use a ghost display adapter which connects directly to the eGPU output port so that apps launched through this ghost display have full acceleration. You can then switch these eGPU-accelerated apps to the internal display or the 5K display.

Step 1:

15″ MBP « » TB3 cable « » Thunderbolt 3 eGPU

Check System Information » Graphics/Displays to see the external graphics card is showing with Metal support. Run an OpenCL app such as Luxmark to confirm the eGPU is working with your MacBook Pro.

Step 2:

15″ MBP « » TB3 cable « » Thunderbolt 3 eGPU « » Ghost Display adapter

Make sure you can switch apps from the ghost display back to the internal display. Once you accomplish this, proceed to add the 5K Thunderbolt 3 display into the mix.

Step 3:

5K TB3 Display « » 15″ MBP « » TB3 cable « » Thunderbolt 3 eGPU « » HDMI adapter

At this point there should be 3 displays: 5K, MBP internal, and ghost. The ghost display should be set as primary so that all apps are launched through it by default with eGPU acceleration. You would then proceed to switch the app to the 5K display through the use of Spectacle.

 

[JayMBP]

Thanks! I will look into it. Will report back my findings when all the components are here.

 

[richinaus]

I wrote this overview of this process in a recent thread: The key is to use a ghost display adapter which connects directly to the eGPU output port so that apps launched through this ghost display have full acceleration. You can then switch these eGPU-accelerated apps to the internal display or the 5K display.

Step 1:

15″ MBP « » TB3 cable « » Thunderbolt 3 eGPU

Check System Information » Graphics/Displays to see the external graphics card is showing with Metal support. Run an OpenCL app such as Luxmark to confirm the eGPU is working with your MacBook Pro.

Step 2:

15″ MBP « » TB3 cable « » Thunderbolt 3 eGPU « » Ghost Display adapter

Make sure you can switch apps from the ghost display back to the internal display. Once you accomplish this, proceed to add the 5K Thunderbolt 3 display into the mix.

Step 3:

5K TB3 Display « » 15″ MBP « » TB3 cable « » Thunderbolt 3 eGPU « » HDMI adapter

At this point there should be 3 displays: 5K, MBP internal, and ghost. The ghost display should be set as primary so that all apps are launched through it by default with eGPU acceleration. You would then proceed to switch the app to the 5K display through the use of Spectacle.

Hey Mr Sage,

You replied to me before, which I was very grateful for.

So, overall you would recommend having a display that can connect straight out of the eGPU. This would remove the need for the ghost hdmi and also provide a speed increase through simplifying and having a direct connection rather than faking a display which would use some of the capacity of the GPU.

Very exciting times I think. Apple should develop this, as it is the perfect solution to a laptop for a pro user. It can act as a hub, space for additional ssd and the eGPU [basically a modular pro hub for the laptops] - this would be so perfect for me. It would also allow Apple to maintain their super thin computers and still provide for the pros. No more whinging [if ever possible]

 

[theitsage]

Using an external display connected to the eGPU directly is the best option. There are a number of 5K displays which use a dual DisplayPort configuration. It's confirmed to work in Windows via eGPU and most likely to work in macOS as well.