[Salty]

Okay so years ago we heard about the big possibility of external GPUs operating via Thunderbolt, but nothing ever came of that. Apple's laptops aside from the 15 inch Pro all have integrated graphics, but there are a lot of apps, (games, graphics apps, video editors, 3D) that can make use of a good ol discrete GPU.

So, is there any technical reason that the next Thunderbolt monitor couldn't come with a dedicated GPU inside? Now, realistically I doubt Apple wants me finding an excuse to not upgrade my 2011 MacBook Pro (It still chugs along pretty well!) But wouldn't it be cool if you could have your crazy thin MacBook, (or Pro or Air) and then come home and connect one cable that not only connects all your USB peripherals and power like it does now, but ALSO hooks you up to a crazy fast GPU so that you can work on whatever you need to work on without having your poor thin MacBook struggling to power that gorgeous 5K display?

(Mostly I'd just want this because I think it would work great with the Affinity Photo and Designer apps I've started using which I do notice are a bit taxing for my poor MacBook's GPU.)

[CharlesS]

I'd expect Apple's next monitor to be based on USB-C, rather than Thunderbolt. Thunderbolt isn't universally available across Apple's lineup anymore.

[P]

Thunderbolt 3 uses USB-C ports, so they could use the Thunderbolt 3 protocol over USB-C ports.

And yes, you could absolutely put the GPU in the display. I think I even suggested it here before at some point. Even better, with USB 3.0 you could have the one single cable provide power to the laptop. There is some movement behind external GPUs again, showing up at some conferences, and AMD is making a push to standardize it. They all use Thunderbolt 3, so absolutely, you could do this.

Will Apple, though? I doubt that. Apple has been pushing Intel hard for more powerful integrated graphics, and we will hopefully see some of that when the 13" Skylaye update hits. That should be more than enough for anything not gaming at Retina resolutions, and Apple never cared much about MAc gaming.

[subego]

Can we just make it so I can't accidentally jam a Tbolt plug in upside down?

[Waragainstsleep]

You can get enclosures to use PCI-E cards externally via Thunderbolt, this has been the case for some time. They aren't cheap though.

[abbaZaba]

I was disappointed in lack of new products in the external GPU connected via Thunderbolt. Seems like a no brainer, but it really hasn't gotten off the ground too much.

Shoving a GPU into a new TB monitor would be very enticing and could distinguish the line-up from other displays. I wonder why that couldn't be on the roadmap.

[reader50]

Barefeats recently did a test using a cylinder MacPro + GTX Titan X in a TB2/PCIe enclosure, vs being in a 2010 Mac Pro in a native PCIe slot. Also compared to the 2013 Mac Pro with D700s.

The Titan X in PCIe box generally outperformed the dual D700s. However, the Titan X in native PCIe slot almost always outperformed the cylinder + expansion box version. I'd expect different results if Thunderbolt 3 were available.

Based on the results, I expect a lower GPU (say GTX 970 or lower) would run over TB2 without being choked. So a monitor + midrange GPU should work just fine.

[P]

TB2 is an x2 PCIe 3.0 slot, and TB3 is an x4 3.0 slot IIRC. NVidia famously disables SLI unless both cards have at least an x8 link, but a 2.0 x8 slot is allowed (because nVidia logic), so TB3 might be enough. AMD is less picky, and I think in the tests I have seen, an x4 link has only very minor impact on performance - less than 1 FPS average.

In general, the more memory the GPU has, the less important the link bandwidth is.

[P]

AMD just added support for hotswapping GPUs, so you can connect to an external box with a GPU and use it without rebooting. They're calling it "Xconnect" and it is clearly aimed at external GPUs - or "eGFX" as AMD is now calling it. Gotta love marketers.