So, this is super, super weird.
I've got a 2019 Mac Pro spec'd out with the Radeon Pro Vega II Duo (MPX module), and two Pro Display XDRs attached to the VII Duo via Thunderbolt 3. As officially supported, of course:
Prior to purchasing this Mac Pro, I was using an eGPU (Sonnet Breakaway Box) with an AMD Radeon Pro WX 9100 — again, an officially supported configuration!
I have non-Apple displays I need to drive, as well as the Pro Display XDRs; when purchasing the Mac Pro, my plan was to simply move my WX 9100 (an expensive piece of kit on its own!) into the Mac Pro (isn't that the whole point of the return to the standardized, expandable chassis? ), and continue using it to push my non-Apple pixels.
Well, bad luck:
Whenever a second graphics card is installed in my Mac Pro — not even connected to any displays! — the Vega II Duo will only drive a single Pro Display XDR at full resolution.
If I connect the second XDR to my VII Duo, it, oddly, happily reports that it's running at full 6016×3384; but text is visibly fuzzy; it very definitely looks like it's being downscaled (poorly!) to 5k. It's especially obvious that something is wrong, as it's sitting right beside another XDR that's actually functioning at full, sharp 6k.
Further oddness: With the WX 9100 installed, I have to boot up with only a single XDR connected to the VII to get either of them to function at 6k; if I boot the machine with the WX 9100 installed *and* two XDRs connected, both XDRs are fuzzy-6k-scaled-up-from-5k.
And the final odd component here? Everything works swimmingly if I connected the WX 9100 to the Mac Pro in my eGPU chassis. That's right, there's 6 unpopulated PCIe slots in this picture, and yet I'm using an eGPU chassis, because that's the only way to get all my displays working:
At this point, I feel I may be the only person, including engineers at Apple, who's ever plugged an eGPU into a Mac Pro. Ugh. >,>
So, tl;dr:
I've got a 2019 Mac Pro spec'd out with the Radeon Pro Vega II Duo (MPX module), and two Pro Display XDRs attached to the VII Duo via Thunderbolt 3. As officially supported, of course:
Prior to purchasing this Mac Pro, I was using an eGPU (Sonnet Breakaway Box) with an AMD Radeon Pro WX 9100 — again, an officially supported configuration!
I have non-Apple displays I need to drive, as well as the Pro Display XDRs; when purchasing the Mac Pro, my plan was to simply move my WX 9100 (an expensive piece of kit on its own!) into the Mac Pro (isn't that the whole point of the return to the standardized, expandable chassis? ), and continue using it to push my non-Apple pixels.
Well, bad luck:
Whenever a second graphics card is installed in my Mac Pro — not even connected to any displays! — the Vega II Duo will only drive a single Pro Display XDR at full resolution.
If I connect the second XDR to my VII Duo, it, oddly, happily reports that it's running at full 6016×3384; but text is visibly fuzzy; it very definitely looks like it's being downscaled (poorly!) to 5k. It's especially obvious that something is wrong, as it's sitting right beside another XDR that's actually functioning at full, sharp 6k.
Further oddness: With the WX 9100 installed, I have to boot up with only a single XDR connected to the VII to get either of them to function at 6k; if I boot the machine with the WX 9100 installed *and* two XDRs connected, both XDRs are fuzzy-6k-scaled-up-from-5k.
And the final odd component here? Everything works swimmingly if I connected the WX 9100 to the Mac Pro in my eGPU chassis. That's right, there's 6 unpopulated PCIe slots in this picture, and yet I'm using an eGPU chassis, because that's the only way to get all my displays working:
At this point, I feel I may be the only person, including engineers at Apple, who's ever plugged an eGPU into a Mac Pro. Ugh. >,>
So, tl;dr:
- Is anybody else currently running MPX and non-MPX graphics cards, simultaneously, in a Mac Pro?
- If so, are you experiencing any problems with display resolutions?
- Has anyone seen a Pro Display XDR reporting a resolution of 6016×3384, while clearly not being there? /=