This was on a Hackintosh? I am surprised the AMD's didn't work. Did you verify that both of the DisplayPort connections that you used work, by using a separate display for each?
Yes, it's with the amd. And the screen works just fine as well as the current connection, booting under Windows give me 5K
You're saying that the 1080ti and the AMD cards all worked at 5K 60Hz? Does the HP z27q have an onscreen menu that states the current timing is 5K at 60Hz to verify the connection (like Dell displays have when you go into the menu)? If that's true then I wonder if the Clover boot loader is modifying the graphics to make them incompatible? Or maybe the board id used by Clover makes the graphics mode incompatible and you should try a Mac Pro 2013 board id?
Is this with the Nvidia LG 5K patch (modified for HP) or without? Is this on the Hackintosh or the Mac Pro 2013?
Yes, under Windows or macos (under a real mac), then this screen works at 5K 60Hz.
Clover is configured to be an imac pro, and that screen works on A real imac pro as well (I had one on try for 2 weeks)
What's surprising under the hackintosh set-up, is that it doesn't detect when screen are hot plugged. It stays under the configuration it got booted under.
Eg if I boot with two screens, then the two screens work (albeit with the wrong resolution on the z27q).
If I unplug one screen like the main one, it doesn't reconfigure the 2nd screen to become the primary one like it does on a normal mac.
If I boot with just one screen and once finished I plug another, then the new screen will stay black.
Some of the comments here talks about starting with the 5K screen not connected and then plugin made it work. Not working with the Vega.
Maybe that's what I need to figure out first, how to mac the graphic card work with hot plugged screen,
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