Late 2019 Mac Pro PCIe Slots and Thunderbolt 3 AIC Apple I/O Card
 

Late 2019 Mac Pro PCIe Slots and Thunderbolt 3 AIC Apple I/O Card  

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itsage
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With the introduction of the mid 2019 Mac Pro, Apple has brought internal PCIe slots back in a tower form factor. The excitement ends here for me. They priced me out completely. What I found most intriguing is the Thunderbolt 3 add-in card. This means when Thunderbolt 4 becomes available it’s possible to upgrade (and hopefully used 2019 Mac Pro are within reach by then). It might be a possibility for the classic Mac Pro to use this AIC if it’s available through third party.

Above is my guess of the PCI Express lane allocation to each slot. The CPU has 64 lanes so a PCIe switch is likely hosting slot 5 to 8. The MPX with its use of a modified/extended slot is pretty cool. From what I gathered Apple routed the two Thunderbolt 3 controllers on the MPX graphics card to a x8 PCIe connection. In a fully configured Mac Pro, there are 6x TB3 controllers and 12x TB3 ports.

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mac_editor
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Apple: Here’s the new Mac Pro.
Me: Seems nice, monitor looks great.
Apple: Starts at 5999$.
Me: Well....
Apple: Here’s the new Apple Pro Display XDR.
Me: This is great.
Apple: Costs 4999$.
Me: Oh, well....
Apple: The stand is sold separately and costs 999$.
Me: ...

That stand should have a f***ing GPU in it, a good one at that.

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nu_ninja
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I mean, the hardware specs look very impressive and I'd be lying if I said I didn't want one, even if I don't know what I would do with it.

But I get the feeling even Apple doesn't really know what they want to do with this. The base iMac Pro is $1000 cheaper and comes with a 5k display attached. Sure it's not as modular, but the CPU and RAM are still socketed and with an eGPU you could theoretically upgrade the graphics as well. I actually wouldn't be surprised if the price point is deliberately higher so it doesn't compete with the iMac Pro.

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Ningauble77
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2019 Mac Pro was announced today with 580x base gpu but option for either single or dual Vega 20- based "Radeon Pro Vega II" cards, so hopefully Radeon VII drivers will improve as we approach the fall.  Also gives little hope to nvidia drivers going forward, considering the Mac Pro has PCIe slots, but semi-proprietary auxiliary connectors on the Graphics Cards to feed DisplayPort from the slots to the TB3 ports and may not even work with generic off-the-shelf GPUs.  Also had a bunch of pro-app companies announce Metal support for their software, some of whom I believe currently perform best with CUDA.

2019 16 Macbook Pro + Core v2 + Radeon VII MacOS 10.15.1
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goalque
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Posted by: Ningauble77

but semi-proprietary auxiliary connectors on the Graphics Cards to feed DisplayPort from the slots to the TB3 ports and may not even work with generic off-the-shelf GPUs.

No word about standard graphics cards. I was wondering if you can combine:

"Up to 300W auxiliary power via two 8-pin connectors"

and

"Three full-length PCI Express gen 3 slots
One x16 slot; two x8 slots
75W auxiliary power available"

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OliverB
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Posted by: Ningauble77

2019 Mac Pro was announced today with 580x base gpu but option for either single or dual Vega 20- based "Radeon Pro Vega II" cards, so hopefully Radeon VII drivers will improve as we approach the fall.  Also gives little hope to nvidia drivers going forward, considering the Mac Pro has PCIe slots, but semi-proprietary auxiliary connectors on the Graphics Cards to feed DisplayPort from the slots to the TB3 ports and may not even work with generic off-the-shelf GPUs.  Also had a bunch of pro-app companies announce Metal support for their software, some of whom I believe currently perform best with CUDA.

So, the trashcan is past, they return to PCIe-slots? Interesting...

2018 15" MBP & 2015 13" MBP connected to RTX2080Ti GTX1080Ti GTX1080 Vega56 RX580 R9-290 GTX680


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Ningauble77
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Posted by: goalque
Posted by: Ningauble77

but semi-proprietary auxiliary connectors on the Graphics Cards to feed DisplayPort from the slots to the TB3 ports and may not even work with generic off-the-shelf GPUs.

No word about standard graphics cards. I was wondering if you can combine:

"Up to 300W auxiliary power via two 8-pin connectors"

and

"Three full-length PCI Express gen 3 slots
One x16 slot; two x8 slots
75W auxiliary power available"

I just noticed those 8-pin connectors mentioned on the tech specs page... in the presentation it kinda looked like the additional power and tb3 displayport connectors were part of the slot.  I guess we will find out soon enough.

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joevt
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Posted by: goalque
Posted by: Ningauble77

but semi-proprietary auxiliary connectors on the Graphics Cards to feed DisplayPort from the slots to the TB3 ports and may not even work with generic off-the-shelf GPUs.

No word about standard graphics cards. I was wondering if you can combine:

"Up to 300W auxiliary power via two 8-pin connectors"

and

"Three full-length PCI Express gen 3 slots
One x16 slot; two x8 slots
75W auxiliary power available"

I think the tech specs say there's four 8 pin connectors (two per MPX bay). This is listed as an alternative, if you don't use an MPX module, which implies using standard graphics cards is an option.

Too bad they don't offer a Thunderbolt routing option for standard graphics cards. A third party could maybe create an adapter that exposes the DisplayPort paths of the MPX connector.

The slots are (from the top):

  • Single wide:
    • 8: x4
    • 7: x8
    • 6: x8
    • 5: x16
  • Double wide:
    • MPX Bay 2:
      • 4: x16 double
      • 3: x16 double
    • MPX Bay 1:
      • 2: x8 double
      • 1: x16 double

This picture is probably the connectors for the PCIe power cables.

PCIe power connectors

For slots 5 to 8, it appears to be one 6 pin (75W).
For slots 1 to 4, there appears to be four 8 pin (150W each).
I don't think these are used by the MPX modules. They get 475W from the MPX slot and 75W from the PCIe slot.

I don't see how DisplayPort gets to the I/O card. Are the signals in the PCIe slot? How can that be? That I/O card slot is obviously a propriety non-standard PCIe slot.

I:O card slot

The I/O card slot appears to block cards longer than x8 (there's a key in the middle). The visible lower x8 pins (fingers? contacts?) are formed to contact both sides of a standard PCIe card edge. The upper x8 part of the slot doesn't have visible pins, or they are arranged differently than PCIe pins. These are probably USB and DisplayPort signals. The USB probably comes from the chipset, so that the I/O card doesn't need a bridge chip to support a USB controller and a Thunderbolt controller. Probably the Thunderbolt controller is on the card. The proprietary I/O card slot may indicate that the I/O card cannot fit in a standard PCIe slot.

The two 10Gb Ethernet ports are down by the power plug and not part of the I/O card (the tech specs should format that text better to make it more clear).

Ethernet ports

With the I/O card, there are four Thunderbolt 3 ports (two on the top of the case, and two on the I/O card). This means there are two controllers which can take two DisplayPort signals each (four total). But the AMD Radeon Vega II MPX Module only supplies two DisplayPort signals. Does this mean two of the Thunderbolt ports cannot do DisplayPort when you only have that MPX Module? Or is there an internal MUX like in the Mac Mini 2018 that routes two DisplayPort signals to the four DisplayPort inputs of the two Thunderbolt controllers?

There is no mention of what the two SATA ports, USB port, and 10 pin plug are for.

Internal ports

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Eightarmedpet
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I like it, but at that price I’m out...  my hopes for a tb3 equipped Gpu were raised then dashed...  le sigh. 

Thinking about it though, this would be total overkill for me.

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OliverB
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The price is within the to be expected boundaries. No news here.
1.5 TB RAM may be enough for image processing.

In the video they say something like "with two MPX Modules (can) create the world's most powerful graphics card". What exactly is this most powerful graphics card? It's not supposed to be the RX580, the only one I can find on that site.

Edit: If found it here.
"There will also be a version with two Radeon Pro Vega II GPUs, which Apple called "the world's most powerful graphics card."

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joevt
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Posted by: itsage

Above is my guess of the PCI Express lane allocation to each slot. The CPU has 64 lanes so a PCIe switch is likely hosting slot 5 to 8. The MPX with its use of a modified/extended slot is pretty cool. From what I gathered Apple routed the two Thunderbolt 3 controllers on the MPX graphics card to a x8 PCIe connection. In a fully configured Mac Pro, there are 6x TB3 controllers and 12x TB3 ports.

Slot 4 is x16. I agree that it is probably not usable when MPX bay 2 x8 connector is used.

But the tech spec imply Slot 2 is usable when MPX bay 1 x8 connector is used. The AMD Radeon Pro 580X Module is only half the width of the AMD Radeon Pro Vega II Modules and thus allows using slot 2 when installed in slot 1. This is probably why  slot 2 is x8 instead of x16.

If all 64 lanes are used by slots 1 to 4 then where do the lanes for the other slots come from? Is it possible the Apple quote of "64 lanes" for the processor also includes lanes from the PCH? The lanes from a PCH would only be good for x4 slots. Therefore, there should be a switch chip somewhere.

About the x8 MPX slots:
The MPX slots have eight lanes for two Thunderbolt 3 controllers. They are probably configured as separate x4 links so that no extra switch is required. It might be interesting if those slots supported an x8 mode for future MPX modules. That would mean the slots support bifurcation.

About the AMD Radeon Pro 580X:
It says it supports two 5K displays. That might only refer to the dual DisplayPort 1.2 variety of 5K (10 bpc) display. It might support four 5K 16:9 (8 bpc) DisplayPort 1.4 displays or four 5K2K 21:9 (10 bpc) ultra wide DisplayPort 1.4 displays.

About the AMD Radeon Pro Vega II:
Four Thunderbolt 3 ports (four DisplayPort connections), one HDMI 2.0 port, and two DisplayPort connections routed to the system means 7 outputs, but Radeon cards only support 6. There's a MUX somewhere in there to disable an output when another output is used.
It says three 5K displays can be used simultaneously. That probably means LG UltraFine 5K (dual displayPort 1.2), one per Thunderbolt controller (two from the card and one from the system).
It says only two 6K displays can be used simultaneously. Does that mean one of the Thunderbolt controllers is Alpine Ridge, or doesn't support DisplayPort 1.4? Or does it mean the Vega II can't output that many pixels?

About the AMD Radeon Pro Vega II Duo:
The picture shows what's probably a PCIe switch chip (next to the x16 PCIe connector) which supports connecting two GPUs to a single slot. It's probably a 48 lane switch with 16 lane upstream and two 16 lane downstream links.
There are two GPUs, each can support 6 displays, but it only support 8 displays. I guess Apple didn't want to add two more Thunderbolt controllers and/or four more ports, because they take space and reduce air flow (and Thunderbolt controllers take more power).
Four Thunderbolt 3 ports (four DisplayPort connections), one HDMI 2.0 port, and four DisplayPort connections routed to the system means 9 outputs. That should be doable with two GPUs, but maybe they used the same MUX as the non-Duo.
The note about three 5K for the non-Duo applies for the Duo (in this case, four 5K). Possibly eight DisplayPort 1.4 8 bpc displays might be supported.
The Duo supports the same number of 6K as 5K, possibly because two are powered by each GPU, so the note about only two 6K being supported for the non-Duo doesn't apply.

About using two MPX modules:
There are only two Thunderbolt 3 controllers on the system which can accept up to four DisplayPort connections from MPX modules. An MPX module can have two or four DisplayPort connections. If you connect two modules, which DisplayPort connections are used?
The Vega II (non-duo) module only has two DisplayPort connections. If you connect two of those modules, do you get four DisplayPort connections, or only two?

About the Apple Pro Display XDR 6K display:
6016 x 3384 60 Hz 10 bpc requires more bandwidth than DisplayPort 1.4 (1289.81 MHz required, 864 MHz available) or dual DisplayPort 1.2 (661.56 MHz required, 576 MHz available) can support. Therefore, it either uses DisplayPort 1.4 with Display Stream Compression (DSC), or it uses dual DisplayPort 1.4 over Thunderbolt (36.6 Gbps). It's probably dual DisplayPort 1.4 (like the Dell 8K 8bpc display), since the 6K display does not include a second Thunderbolt 3 port (the second Thunderbolt 3 port is used internally to extract the second DisplayPort 1.4 signal). The 6K might work with dual DisplayPort 1.2 at 8 bpc (720 MHz available) but not single DisplayPort 1.4 8 bpc (1080 MHz available).

MHz (pixel clock timing) calculated using CVT-RB. Available MHz calculated using max DisplayPort bandwidths, assuming no overhead other than that bits are transferred during blanking periods at the same rate as active periods. The pixel clock timing for Dual DisplayPort is for a single 3008 x 3384 60 Hz signal using CVT-RB. Thunderbolt bandwidth calculation assumes no blanking period pixels are transmitted (otherwise, Thunderbolt max of 40 Gbps would be exceeded).

36.6 Gbps doesn't leave a lot of room for I/O, so the display only has three USB 2.0 ports ( (type-C connector). How many USB 2.0 devices use type-C connectors? None or very few, but the USB-C ports are prettier next to the Thunderbolt 3 port, and they allow for more power for charging. The tech specs say "For Mac models with Thunderbolt 3 driving Pro Display XDR at 5K resolution, USB-C ports have USB 3.1 Gen 1 data transfer speeds."

I wonder if 5K on the XDR uses Dual DisplayPort 1.2 mode like the UltraFine 5K (10 bpc) or single DisplayPort 1.4 mode (8 bpc without DSC). Probably the former because 10 bpc is more desirable and I think Apple is referring to Macs that don't have DisplayPort 1.4 and Titan Ridge.

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joevt
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Since the Apple Pro Display XDR 6K display uses a Titan Ridge controller, I wonder if it has any USB-C DisplayPort alt mode input modes? They specifically mention the "upstream port for the Mac Pro and other Thunderbolt 3 hosts" which leaves out USB-C (not Thunderbolt) hosts such as the MacBook, iPad Pro, etc.

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joevt
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More notes about the Apple Pro Display XDR 6K display. As discussed in another thread, Catalina has mtdd files in the Overrides folder for the display. It confirms dual cable DisplayPort 1.4 connection for 6K (648MHz), and also includes a dual cable DisplayPort 1.2 connection for 5K (481MHz). In SwitchResX, the 6K timing will report as approximately 1286MHz and the 5K timing will report as approximately 934MHz. Single cable 4K modes are supported (and one 1440p60 mode). Someone with a Titan Ridge Thunderbolt controller that has a single DisplayPort 1.4 input will have to test if single cable 5K60 8 bpc mode is supported. Someone will also have to test dual cable DisplayPort 1.2 for 6K60 8 bpc. Lower refresh rates (down to 47.95Hz) are listed but they don't lower the pixel clock. Someone will have to try lower pixel clocks for dual cable modes (by editing the mtdd, its overlay, and maybe the override file) to see if a 6K 10 bpc mode can be supported with just dual cable DisplayPort 1.2. SwitchResX has no support for creating dual cable modes but I don't think we've ever seen a display that supports more than one dual cable mode. Does a backendtiming in a mtdd file need to exist in the real EDID? Does SwitchResX custom resolutions affect dual cable displays (other than scaled modes)? I don't think so (I've tried on a Dell UP2715K 5K display).

Dell UP3218K 8K display uses two 1058.80 MHz DisplayPort 1.4 signals. Considering only active pixels at 8 bpc, that's 23 Gbps (best case without DSC) and therefore cannot be driven by a single Titan Ridge Thunderbolt 3 port (limited to 40 Gbps).

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joevt
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I saw a screen shot of a hackintosh (actually a real Mac Pro 2010) identifying itself as the Mac Pro 2019 using OpenCore boot loader.
 #80 

It shows a "PCI Cards" tab in "About This Mac". What's interesting is that for each PCIe slot row, there is a x0 column, and an A and B column. The most interesting thing is the "Expansion Slot Utility..." button and the "PCI Card Upgrade Instructions" buttons. The Expansion Slot Utility hasn't existed since MacPro2,1 (2006?). It lives in the /System/Library/CoreServices/ folder.

Further searches found this which shows the Expansion Slot Utility.
 #16 

A and B are two pools of bandwidth. You can select which pool each slot uses manually, or select an option to assign the pools automatically.

It seems that the utility will also show current and max PCIe link speed and width (unlike System Information.app which only shows the speed at startup). But it might only do that if they are not optimal?

 

For the Apple Pro Display XDR, there appears to be a new command line utility for diagnosing problems with the display at
/System/Library/Extensions/AppleGraphicsControl.kext/Contents/MacOS/DisplayDiagnose

This is next to the AGDCDiagnose utility which I use to get EDIDs from displays (works with dual link SST displays like the LG UltraFine 5K) and DisplayPort connection info (link speed and link width).

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mac_editor
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So the “wheels” add-on on for the Mac Pro costs 400$ folks. Hope it has cruise control, and a jet engine too.

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joevt
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Some interesting stuff:

I see for the first time mention of Display Stream Compression (DSC) on Apple's support pages but only with the AMD Radeon Pro W5700X
https://support.apple.com/kb/SP797?locale=en_US

For the Apple Pro Display XDR, the compatibility list doesn't include Macs that are limited to DisplayPort 1.2? I guess that makes sense since DisplayPort 1.4 is required for 6K (without DSC) and HDR. But the mtdd files in the macOS Overrides folder include a 5K timing similar to the LG UltraFine 5K so maybe it can work with DisplayPort 1.2?

Belkin is selling PCIe cables for the Mac Pro.
https://www.apple.com/shop/product/HMUJ2ZM/A/belkin-aux-power-cable-kit-for-mac-pro

Maybe with DSC the AMD Radeon Pro W5700X will support single cable DisplayPort 1.4 8K displays?

The mtdd file for the Apple Pro Display XDR (with product ID ae2e) has a new flag (new to Catalina 10.15.2) called "DisableDSC" set to true. But there are 5 other Apple Pro Display XDR product IDs - not sure how they work - different connection methods use different product IDs?

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itsage
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@joevt Regarding Mac compatibility with the Apple Pro Display XDR monitor, is the limitation due to DisplayPort 1.2 or not having a Titan Ridge Thunderbolt 3 controller? Funny they showed a Radeon RX 5700 XT GPU on Belkin PCIe cables product page but Apple has not made their Radeon Pro W5700X available. It’s a shame the base configuration comes with a 3 year old graphics card.

Here is the support article with instructions on replacing different components inside the 2019 Mac Pro. I’m interested in knowing whether the Apple I/O card would be available for purchase separately. It should theoretically work in the older Mac Pro tower.

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joevt
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@itsage

Well, Titan Ridge doesn't add anything except DisplayPort 1.4. Mac mini has Titan Ridge but only DisplayPort 1.2.

The AMD Radeon Pro 580X is the only one that is half height so it doesn't block slot 2 which can be used for something else. Slot 2 is enabled because the 580X MPX doesn't use the x8 for Thunderbolt controllers. But shouldn't this also be true for slot 4? Maybe, but buying two 580X MPX is not an option and you can't buy it separately like the Vega II MPX modules.

Slot 1/Slot 2 (MPX bay 1) is preferred for graphics because a full height MPX module won't waste the PCIe lanes of slot 2 (which is only x8 and will be used by the Thunderbolt controllers of the MPX module). But in MPX bay 2, you're wasting 8 lanes of slot 4 with a full height MPX module. Can you squeeze in there an ADT-Link cable to save those 8 lanes? This would require the x16 slot to have a different root port than the ports used for the Thunderbolt controllers slot of the MPX bay.

The Apple I/O card slot is a PCIe x4 slot with an extra connector for connecting two DisplayPorts to a Thunderbolt controller. The connector probably has two USB 3.1 Gen 2/USB 2.0 connections for the USB type A ports. There might by an additional two USB 2.0 connections to provide USB 2.0 to the Thunderbolt 3 ports like the GC-TITAN RIDGE or Mac Mini 2018's Thunderbolt ports. There could be some Thunderbolt header connections as well. The support documents don't have pictures of the I/O card. There is a drawing but it doesn't show anything.

Well, maybe the Apple I/O card can work without the extra connector.

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joevt
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About the MPX slots (DisplayPort):
The first bay (bottom slot) has 4 DisplayPort connections to the two Thunderbolt controllers. This supports the MPX 580X and MPX Vega II Duo.

The second bay only needs two in case the first slot is populated by a MPX W5700X or MPX Vega II - if you consider that the first bay should be populated first by a MPX GPU. To test this, use an MPX 580 in bay two and no MPX module in bay one - if a GPU is required in bay 1 then use a non MPX GPU. Next, connect 4 displays to the Thunderbolt ports.

If the second bay only has two DisplayPort connections, then the DisplayPort mux for the two Thunderbolt controllers only needs 6 inputs (instead of 8) and 4 outputs. 4 outputs is required so that a single MPX module having two DisplayPort connections can drive a display no matter which Thunderbolt controller it is connected to (like the Mac mini 2018).

I can't think of a reason for the second bay to have four DisplayPort connections except to allow a non-MPX GPU device in bay 1.

About the AMD Radeon Pro W5700X:
This is similar to the Vega II, except this allows three XDR displays instead of just two. This suggests the 6K display limitation with the Vega II is because of bandwidth. But all the other specs of the Vega II are superior to the W5700X. Maybe it has something to do with the W5700X's support for DSC.

In order of bandwidth (60 Hz, 10 bpc), we have:
1) 2 x 6K (73 Gbps)
2) 3 x 5K (80 Gbps)
3) 6 x 4K (90 Gbps)
4) 1 x 6K + 4 x 4K (96 Gbps) (is this possible with the Vega II?)
5) 2 x 6K + 2 x 4K (103 Gbps) (is this possible with the Vega II?)
6) 3 x 6K (110 Gbps) (not possible with the Vega II)
It's strange that a graphics card can have a display limit that is less than the sum of the limit of each output port that can be used simultaneously. Nvidia cards have 5 outputs but only 4 are usable at the same time (except if two are used by a single display - such as a dual cable 5K display). AMD cards can support 6 outputs at the same time:
7) 6 x DisplayPort 1.4 (156 Gbps)

I've never seen this limit occur in real life (never had that many 5K or 6K displays).

3 x 6K is still on top if you use 4096x2304 for the 4K displays instead of 3840x2160 but it would be interesting if using 4096x2304 would break #3 for the Vega II, or (#5 and #6 if they did work for the Vega II).

8 displays for a Vega II Duo.

About dual AMD Radeon Pro 580X:
This is not a build option and there's no option to buy the 580X separately. But if you could have a second, then the second 580X would allow you to add only two more 4K HDMI 2.0 displays because there's no more DisplayPort lanes on the motherboard to use. 

About dual AMD Radeon Pro Vega II or W5700X:
Two of these would allow double the number of displays (2 DisplayPort lanes per card = 4 total = number of available motherboard DisplayPort lanes).

About dual AMD Radeon Pro Vega II Duo:
A single Vega II Duo allows 8 x 4K or 4 x 6K (should have been 9 x 4K but I guess the HDMI port acts like the HDMI port of the Vega II?). The second Vega II Duo adds only 4 more DisplayPort (the Thunderbolt ports of the card - allowing 4 x 4K or 2 x 6K) and zero, one or two HDMI ports:

  1. All four motherboard DisplayPorts come from from bay 1. Result: no change in first card's capability (8 x 4K or 4 x 6K); second card has reduced capabilities:
    1. HDMI 2.0 port is tied with rear GPU Thunderbolt ports: Result: additional 4 x DisplayPort (4 x 4K or 2 x 6K), or 3 x DisplayPort + 1 x HDMI (3 x 4K or 1 x 6K + 1 x 4K)
    2. HDMI 2.0 port is tied with motherboard DisplayPort: Result: additional 4 x DisplayPort + 1 x HDMI (5 x 4K or 2 x 6K + 1 x 4K)
  2. two motherboard DisplayPorts come from bay 1, two motherboard DisplayPorts come from bay 2. Result: both cards are reduced in capability (6 x 4K or 3 x 6K) plus:
    1. HDMI 2.0 port is tied with rear GPU Thunderbolt ports: Result: no additional display
    2. HDMI 2.0 port is tied with motherboard DisplayPort: Result: additional 4K display.

Total:
1a,2a) 12 x 4K or 6 x 6K
1b) 13 x 4K or 6 x 6K
2b) 14 x 4K or 6 x 6K 

I just don't know how the HDMI port works. To find out, you need five displays. Connect 5 to the GPU. Then try one to HDMI and 4 to motherboard Thunderbolt ports.

Or what if macOS has an 8 display limit? No. 
https://support.apple.com/en-us/HT210228

This post was modified 1 month ago

Mac mini (2018), Mac Pro (Early 2008), MacBook Pro (Retina, 15-inch, Mid 2015), GA-Z170X-Gaming 7, Sapphire Pulse Radeon RX 580 8GB GDDR5, Sonnet Echo Express III-D, Trebleet Thunderbolt 3 to NVMe M.2 case


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itsage
(@itsage)
Illustrious Member Admin
Joined: 3 years ago
 

iFixit posted the full teardown – https://www.ifixit.com/Teardown/Mac+Pro+2019+Teardown/128922

I love the multipoint compression latch handle mechanism.  

This post was modified 1 month ago

external graphics card builds
best laptops for external GPU
eGPU enclosure buyer's guide


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joevt
(@joevt)
Prominent Member
Joined: 2 years ago
 

96 lane switch (possibly two upstream x16 which might be how the Pool A/Pool B thing works).

I saw the JHL7540 for the top Thunderbolt 3 ports. They didn't show the I/O card.

Don't know what the serial port controller is for. Connection to an internal device? MPX slot? I/O card slot? Hidden COM header?

You can count the pins on the I/O connector slot and the MPX slots. There appear to be enough for the connections we know about (I/O card: USB 3.1 gen 2 x2, USB 2.0 x2, DisplayPort x4x2, audio, Thunderbolt header; MPX slot: PCIe x8, DisplayPort x4x4).

I would like to see an IORegistryExplorer save file.

Mac mini (2018), Mac Pro (Early 2008), MacBook Pro (Retina, 15-inch, Mid 2015), GA-Z170X-Gaming 7, Sapphire Pulse Radeon RX 580 8GB GDDR5, Sonnet Echo Express III-D, Trebleet Thunderbolt 3 to NVMe M.2 case


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