NVidia or Radeon GPUs that support more than 4 active displays

Question

Are there any recent Nvidia or Radeon GPUs that support more than 4 active displays using one card? I've tried a few that have 5 ports but they usually only allow 3 or 4 active displays at one time. On Linux this is easy to detect using the xrandr --listproviders command, which for my GeForce FTX 970 shows crtcs: 4 meaning it only allows 4 active displays.

Provider 1: id: 0x3f cap: 0x4, Source Offload crtcs: 4 outputs: 8 associated providers: 1 name:nouveau

Which GPUs allow more than 4 displays when using DisplayPort Multi Stream Transport (MST) or other methods of splitting a single port into multiple active displays? All of the Nvidia GPUs that I've checked look like they only support 4 active displays even if they have 5 or 6 different ports.

Answer 1

I saw a footnote on the (now dated) AMD FirePro w7100 data sheet stating:

Three 4K displays at 60Hz requires displays with DisplayPort 1.2 interfaces with support for HBR2 ( for SST ) or HBR2 with MST. Four 4K displays at 30Hz requires displays with at least one DisplayPort interface. Four 4K displays at 30Hz with HDMI 1.4a interface can also be supported via DisplayPort to HDMI adapters that support HDMI 4K output. Six full-HD displays requires DP 1.2 MST hub or at least two monitors capable of DP 1.2 daisy-chaining.

Meaning when using MST you could get up to 6 active displays. I checked the data sheet for the newer AMD Radeon Pro WX 5100 and Pro WX 7100 which state:

Display Output Support (@ 60Hz)
4 @ 1920x1080
4 @ 3840x2160
2 @ 5120x2880
1 @ 7680x4320

But they don't state anything about how many total active displays are supported when using MST. I ended up buying the AMD Radeon Pro WX 5100 and can confirm it supports up to 6 active display engines when two of the inputs use Display Port MST:

xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x5d cap: 0x9, Source Output, Sink Offload crtcs: 6 outputs: 8 associated providers: 0 name:AMD Radeon (TM) Pro WX 5100 Graphics @ pci:0000:01:00.0

The Radeon Pro WX Series Quick Start Guide (which I cannot find an online copy of) also includes more details about the supported display configurations: