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MarciaFunebre

macrumors member
Original poster
Oct 17, 2018
52
20
On the phone an Apple technician told me to bring my 7,1 Mac Pro into the shop for repair after finding out that under About - System report - Thunderbolt there were two busses listed - one with number 2 and number 3. But no number 1.
Somehow I suspect that this could have something to do with the disastrous 10.15.4 update.

Especially those of you who are running on 10.15.3 or earlier, could you please see how many TB3 busses are listed in your System Report?
 

joevt

Contributor
Jun 21, 2012
6,660
4,078
There should be one Thunderbolt bus for the top Thunderbolt ports and another Thunderbolt bus for the I/O card.
Then there should be two Thunderbolt buses more per Vega II or Vega II Duo or W5700X MPX module.
6 is the maximum number of Thunderbolt buses in the MacPro7,1.

I think I remember people complaining about Thunderbolt ports not working in the MacPro7,1 and that the solution is to turn everything off and unplug it for awhile.
 
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Schismz

macrumors 6502
Sep 4, 2010
343
394
Currently have 4 Thunderbolt buses, 0, 1, 2, 3 with Vega Pro II (not Duo). 10.15.4 with no significant issues. Have not installed supplemental update ... just gonna wait for 10.15.5 combo installer, seeing way too much angst online regarding bricking devices with multiple firmware updates; my Mac Pro is experiencing none of these issues, except the top Thunderbolt ports wherein the right-side one was unresponsive until SMC reset. Shutdown, remove power cable for 15 seconds, restart, solved it in my case. No kernel panics, no significant new problems.
 

profdraper

macrumors 6502
Jan 14, 2017
331
250
Brisbane, Australia
Currently have 4 Thunderbolt buses, 0, 1, 2, 3 with Vega Pro II (not Duo). 10.15.4 with no significant issues. Have not installed supplemental update ... just gonna wait for 10.15.5 combo installer, seeing way too much angst online regarding bricking devices with multiple firmware updates; my Mac Pro is experiencing none of these issues, except the top Thunderbolt ports wherein the right-side one was unresponsive until SMC reset. Shutdown, remove power cable for 15 seconds, restart, solved it in my case. No kernel panics, no significant new problems.
FWIW, the latest 10.15.4 update I just updated from 10.15.3 & installed on an Alt Boot drive - is self contained, ie, no longer requires the additional supplemental update.

Generally I agree though, Catalina has been a real dog; hoping 10.15.5 might indeed be the *real thing* and is also noticeable that FCPX, Logic or Pro Aps updates have still not been released yet, not to mention some decent firmware & optimisations for the Vegas - all of which has been usual to optimise following a major system change.
 

MarciaFunebre

macrumors member
Original poster
Oct 17, 2018
52
20
Anyone on 10.15.3 or older with a 580X base model graphic card? Do your TB busses show up as 2 and 3?
 

Schismz

macrumors 6502
Sep 4, 2010
343
394
FWIW: 0 & 1 are the video card (in my case Vega II). 2 is Apple's I/O card, 3 are the ports on top of the MP. If you only see 2 & 3, what's MIA is your video card. I have no idea if this is "normal" for a 580X and someone who has one installed with 10.15.3 would have to answer that.

FWIW, the latest 10.15.4 update I just updated from 10.15.3 & installed on an Alt Boot drive - is self contained, ie, no longer requires the additional supplemental update.

Generally I agree though, Catalina has been a real dog; hoping 10.15.5 might indeed be the *real thing* and is also noticeable that FCPX, Logic or Pro Aps updates have still not been released yet, not to mention some decent firmware & optimisations for the Vegas - all of which has been usual to optimise following a major system change.
Ya, Catalina 10.15.5 for the win? Or maybe stop adding dumb iOS Apps and silly "features" since supply-chain has massive constraints, recession is coming, and your software engineers are sitting at home, so focus on turning 10.16 into another "Snow Leopard" with foundational stability fixes before 10.17 makes it all fall apart again with ARM support.

It's not just the MP, if you go one forum up the tree here to Catalina, this seems to affect everything with a T2 chip, new MacBooks (Pro and Air), etc, etc, etc.
 
Last edited:

Krevnik

macrumors 601
Sep 8, 2003
4,100
1,309
FWIW: 0 & 1 are the video card (in my case Vega II). 2 is Apple's I/O card, 3 are the ports on top of the MP. If you only see 2 & 3, what's MIA is your video card. I have no idea if this is "normal" for a 580X and someone who has one installed with 10.15.3 would have to answer that.

Now I'm curious what a second Vega II shows up as. Allocating 0 & 1 to the MPX slots makes sense to me. I'd expect that the second Vega II would get bus 4 & 5, which I find kinda funny.

On the phone an Apple technician told me to bring my 7,1 Mac Pro into the shop for repair after finding out that under About - System report - Thunderbolt there were two busses listed - one with number 2 and number 3. But no number 1.
Somehow I suspect that this could have something to do with the disastrous 10.15.4 update.

Especially those of you who are running on 10.15.3 or earlier, could you please see how many TB3 busses are listed in your System Report?

For my two bits: There's nothing about this that seems weird to me. The fact that the tech wasn't aware that these buses are 0-indexed, tells me they are supposed to be following a script, maybe not engineering saavy (but tech saavy enough to be dangerous), and departed from the script.

Without any TB3 buses from a GPU, there will be two TB3 buses as has been stated. 1 controller chip = 1 bus. In the Mac Pro, there are no controllers on the logic board. With the 580X, there is only the controller on the I/O PCIe card, and the controller on the I/O daughter-board that holds the top-mounted TB3 ports.

TB3 is such that you can't really get away with putting the controllers very far from the ports, and everything internal to the machine can be done over PCIe for less money (like the bridge for the T2 chip), so I don't even know what a third controller would do.
 
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