Oh wow very cool! This sounds like the solution. Do you know if it works under boot camp as well?
Thanks!!
For me, I was able to get the BM eGPU to work with Windows, but it's a convoluted process (most mac eGPU setups are). I think I posted a build guide at eGPU.io for anyone interested. My Ultrafine 5k and XDR are scaled and are being driven by the D700 through the eGPU so it's scaled and probably takes a bigger performance hit. Reports 3840x2160 4k @150% on the XDR. However, setting the game or app to prefer the eGPU via graphic settings does indeed work and game chews at the eGPU rather than discreet.
Can you verify from the EDID file generated by SwitchResX that it's actually 5k/6k and not upscaled 4k? There should be a MHz entry, where ±500 is 4k and ±900 is 5k
Sure. Seeing 1285.82 MHz @ 59.940Hz reported. Various resolutions reported. Popped over to the 7,1 and both EDID files appear identical. I'm using default "more space setting" 3008x1692" and things look clear and sharp. Having the LG Ultrafine 5k next to it connected to the D700, I can obviously tell when it's scaled.
Just for fun, I just plugged this in via Thunderbolt 2 direct into the 6,1/XDR (TB3/2 adapted) and can report it does in fact drive the display via my D700, but obviously at a scaled resolution. Quality looks about the same as at the LG Ultrafine scaled, I honestly expected it to look worse..
I guess this only works because Blackmagic eGPUs have display out on the second TB3 connector (no other eGPU offers this capability as far as I know). But you pay a lot for that privilege (a second hand Vega 56 and a Razer Core X would cost less than half the price).
Quite correct, that's the only way this works. I happened to have BM eGPU Pro for a MacBook setup I've retired and have since moved the eGPU and LG Ultrafine over to my 6,1. I happened on the eGPU on eBay for a bit of a deal, around $800 USD, so a bit cheaper than new but still agreeably not worth the cost of a $200+ USD Vega 56. It has however been working wonderful for me. The XDR just happens to be here with my 7,1 from my office due to a COVID-19 shelter in place order. So I switch back to my personal 6,1 on the weekend/evenings.