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Pro XDR on Bootcamp: Desktop Resolution vs Active Signal Resolution?
- Thread starter LeonPro
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The Vega II uses two DisplayPort 1.4 HBR3 signals of 3008x3384 (one for the left half of the display and one for the right half) to make a 6016x3384 image on the XDR display. The Vega II can have six DisplayPort 1.4 connections total, two per Thunderbolt bus. For the third pair, you can choose the ports at the top of the Mac Pro, or the ports on the I/O card. I don't know if you can use one connection from the top and another from the I/O card. You can connect 3 XDR displays total even though Apple says only two are supported.
macOS doesn't report active signal resolution or pixel format (it only shows frame buffer resolution and frame buffer pixel format). To see the output signal resolution and output pixel format, you can use the AGDCDiagnose command. With the output from the AGDCDiagnose command, you will see that the XDR is connected using two HBR3 signals.
I think this is the first proof I've seen that Windows can support dual-link SST 6K. I think this only works with a Mac running Boot Camp, since a PC will have a Thunderbolt controller that doesn't have the Apple firmware that allows dual HBR3 signals?
I believe the W5700X and W5500X use DSC to drive the XDR display at 6K with one DisplayPort 1.4 HBR2 signal of 6016x3384. Any PC with a GPU that supports DSC (AMD Navi, Nvidia RTX, Intel Ice Lake) should be able to do that. The Apple support pages says the W5700X and W5500X only support 1 XDR display per Thunderbolt bus, suggesting that DSC isn't used - which seems strange to me. If DSC were used, then you could connect 6 XDR displays to the W5700X and 2 to the W5500X. Maybe there's a limit to the number of total pixels per second allowed by the GPU, or the number of displays that are allowed to use DSC, or whatever.
macOS doesn't report active signal resolution or pixel format (it only shows frame buffer resolution and frame buffer pixel format). To see the output signal resolution and output pixel format, you can use the AGDCDiagnose command. With the output from the AGDCDiagnose command, you will see that the XDR is connected using two HBR3 signals.
I think this is the first proof I've seen that Windows can support dual-link SST 6K. I think this only works with a Mac running Boot Camp, since a PC will have a Thunderbolt controller that doesn't have the Apple firmware that allows dual HBR3 signals?
I believe the W5700X and W5500X use DSC to drive the XDR display at 6K with one DisplayPort 1.4 HBR2 signal of 6016x3384. Any PC with a GPU that supports DSC (AMD Navi, Nvidia RTX, Intel Ice Lake) should be able to do that. The Apple support pages says the W5700X and W5500X only support 1 XDR display per Thunderbolt bus, suggesting that DSC isn't used - which seems strange to me. If DSC were used, then you could connect 6 XDR displays to the W5700X and 2 to the W5500X. Maybe there's a limit to the number of total pixels per second allowed by the GPU, or the number of displays that are allowed to use DSC, or whatever.
