Late 2013 15" MBP 4k@60Hz external monitor integrated GPU

[Flyview]

I'm curious if the A1398 2013 - 2014 15" MacBook Pros can drive an external 4k display at 60Hz over thunderbolt DisplayPort using the integrated GPU. It's working great for me but it's making me use the dedicated GPU. If I force the integrated GPU using gfxStatus, the external display remains black.

Were these MacBooks able to drive external 4k displays at 60Hz when they only came with the integrated Intel Iris Pro graphics and no dedicated Nvidia GPU?

 

[arw]

The resolution doesn't even matter. Apparently no Dual-GPU MacBook Pro can drive an external display without using the discrete GPU. This is a hardware restriction with the output being hardwired to the dGPU.
(This even holds true for my 2019 16" MBP.)

It has been discussed here:

Anyone know how to use an external monitor when ONLY using Intel integrated GPU?

Not possible... the display outputs are physically linked to the dedicated GPU. It is not possible to connect an external display to the integrated GPU in a MacBook Pro. This is true of all generations of dual-graphics Macs.

forums.macrumors.com

I have not found any confirmation of MacBooks with Intel Iris 5200 Pro (IG only) being able to support more than 4K @30Hz.

Although technically, 4K @60Hz via DP is possible with all 2013/2014 MBPs with HQ-series i7 CPUs (like the i7-4750HQ and all other i7-47**HQ, i7-48**HQ and i7-49**HQ).
Via HDMI they are still limited to 4K @30Hz.

On the other hand, all 2013/2014 MBPs that feature the Intel Iris 5100 Pro are limited to 4K @30Hz or 3200x2000 @60Hz even via DP. This applies to all U-series CPUs (all i5 and i7-4558U, i7-4578U).

 

[Flyview]

Thanks for the informative post! I'm curious if anyone's been able to run 4k @ 60hz on the integrated only machines.

 

[Chancha]

Thanks for the informative post! I'm curious if anyone's been able to run 4k @ 60hz on the integrated only machines.

I believe it was 2014 or 2015 until the internal Intel Iris could put out 4k60, on both the 13” and the 15” with iGPU. The ones before needed SwitchResx to enable something like 52 or 54Hz, with macOS restricting to 4k30.