Adding USB 3.0 (and more) to a 2011 Mac

[joevt]

I have a Samsung T5 USB 3.1 gen 2 SSD. It's the boot drive for my Late 2015 21.5" iMac 4K (my main system). It currently does about 430 MB/s read and 420 MB/s write on there (I'm guessing that's without UASP because Mojave shows IOUSBAttachedSCSI.kext as not loaded).

Or that might be the PCIe 2.0 x1 limit of the USB 3.0 controller. Both USB 3.0 and PCIe 2.0 x1 have a 4 Gbps limit, but PCIe protocol overhead might be greater than USB protocol overhead. In that case you would expect USB 3.0 to be faster when connected to a PCIe 2.0 x2 or PCIe 3.0 x1 USB controller (which are usually USB 3.1 gen 2 controllers).

For UASP support, check the ioreg for USB devices with bInterfaceProtocol = 98
ioreg -l | egrep '"bInterfaceProtocol" = [89][08]'

Then check the ioreg for the driver:
ioreg -il | egrep '\+-o IOUSBMassStorage.*Driver '

• 80 (50h - USB Mass Storage Class Bulk-Only (BBB) Transport) and the driver is IOUSBMassStorageDriver
• 98 (62h - Allocated by USB-IF for UAS. UAS is defined outside of USB) and the driver is IOUSBMassStorageUASDriver

See here: #162

 

[joevt]

Beautiful! (Though I'd be really curious as to why this actually happened. Were they trying to install a water cooling block or something?)

To upgrade the GPU?
https://forums.macrumors.com/threads/2011-imac-graphics-card-upgrade.1596614

 

[Anonymous Freak]

Yep, back when I was using my 2011 iMac as my home server, I used a TB dock to give it USB 3.0 to plug in two USB 3.0 hard drives. (And to give it a second Ethernet.)

I also used the iMac in Target Display Mode as an external display connected to my 2012 MBP most of the time. It just sat there being home server/monitor.

I just wish the hacks to allow 2011 iMacs to run newer macOS had kept Target Display Mode support. Once it was two versions out of date, I upgraded to a Mac Mini for server duties and retired the iMac to "kitchen computer" status.

 

[joevt]

I just wish the hacks to allow 2011 iMacs to run newer macOS had kept Target Display Mode support. Once it was two versions out of date, I upgraded to a Mac Mini for server duties and retired the iMac to "kitchen computer" status.

My 2013 iMac (iMac14,2) does Thunderbolt Target Display Mode while running Monterey (connected to a Mac mini 2018 also running Monterey).

 

[Anonymous Freak]

It's the video card in the 2011 being unsupported that does it.

 

[joevt]

It's the video card in the 2011 being unsupported that does it.

I believe Thunderbolt Target Display Mode is supposed to bypass the GPU completely though. Maybe the switch to Thunderbolt input doesn't happen when the GPU is unsupported. What was the last version of macOS that you tried? I think I had an issue with Catalina but Monterey worked ok.

 

[Amethyst1]

Beautiful! (Though I'd be really curious as to why this actually happened. Were they trying to install a water cooling block or something?)

This was for testing GPU upgrades. Watercooling would be cool though!

For UASP support, check the ioreg for USB devices with bInterfaceProtocol = 98
ioreg -l | egrep '"bInterfaceProtocol" = [89][08]'

Thanks. The output of that (on the iMac with the T5) is:

    | |   |   |     |   "bInterfaceProtocol" = 80
    | |   |   |       |   "bInterfaceProtocol" = 80
    | |   |   |         |   "bInterfaceProtocol" = 80
    | |   |   |           |   "bInterfaceProtocol" = 80
    | |   |         |   "bInterfaceProtocol" = 98
    | |   |           |   "bInterfaceProtocol" = 80
    | |   |             |   "bInterfaceProtocol" = 98
    | |   |               |   "bInterfaceProtocol" = 98
      | |   | |     "bInterfaceProtocol" = 80
      | |   | |     "bInterfaceProtocol" = 80

Then check the ioreg for the driver:
ioreg -il | egrep '\+-o IOUSBMassStorage.*Driver '

The output of that is:

    | |   |   |         +-o IOUSBMassStorageDriver  <class IORegistryEntry:IOService:IOSCSIProtocolInterface:IOSCSIProtocolServices:IOUSBMassStorageDriver, id 0x100005707, !registered, !matched, active, busy 0 (1642 ms), retain 9>
    | |   |             +-o IOUSBMassStorageUASDriver  <class IORegistryEntry:IOService:IOSCSIProtocolInterface:IOSCSIProtocolServices:IOUSBMassStorageUASDriver, id 0x1000003a0, registered, matched, active, busy 0 (30 ms), retain 9>

 

[joevt]

This was for testing GPU upgrades. Watercooling would be cool though!


Thanks. The output of that (on the iMac with the T5) is:

    | |   |   |     |   "bInterfaceProtocol" = 80
    | |   |   |       |   "bInterfaceProtocol" = 80
    | |   |   |         |   "bInterfaceProtocol" = 80
    | |   |   |           |   "bInterfaceProtocol" = 80
    | |   |         |   "bInterfaceProtocol" = 98
    | |   |           |   "bInterfaceProtocol" = 80
    | |   |             |   "bInterfaceProtocol" = 98
    | |   |               |   "bInterfaceProtocol" = 98
      | |   | |     "bInterfaceProtocol" = 80
      | |   | |     "bInterfaceProtocol" = 80

The output of that is:

    | |   |   |         +-o IOUSBMassStorageDriver  <class IORegistryEntry:IOService:IOSCSIProtocolInterface:IOSCSIProtocolServices:IOUSBMassStorageDriver, id 0x100005707, !registered, !matched, active, busy 0 (1642 ms), retain 9>
    | |   |             +-o IOUSBMassStorageUASDriver  <class IORegistryEntry:IOService:IOSCSIProtocolInterface:IOSCSIProtocolServices:IOUSBMassStorageUASDriver, id 0x1000003a0, registered, matched, active, busy 0 (30 ms), retain 9>

One disk is using normal BOT driver and another is using UASP. Disconnect one to see which is which. Or look at full ioreg output. There's a script at #160

 

[Amethyst1]

One disk is using normal BOT driver and another is using UASP.

I had an old flash drive connected as well - yanking that confirmed the T5 is using UASP. I've also attached pcitree.sh's output with the Thunderbolt 2 dock to post #22.

 

[joevt]

I had an old flash drive connected as well - yanking that confirmed the T5 is using UASP. I've also attached pcitree.sh's output with the Thunderbolt 2 dock to post #22.

The Thunderbolt 1 host controller is running at PCIe Gen 1 speed again (10 GT/s total) just like when the Kanex KTU10 Thunderbolt 1 dock was connected. Again, this is not a problem since the USB and Ethernet controllers are only 5 GT/s and 2.5 GT/s. It could be a problem if you chained multiple devices and tried an ATTO Disk Benchmark of multiple USB disks at once.

 

[Anonymous Freak]

I believe Thunderbolt Target Display Mode is supposed to bypass the GPU completely though. Maybe the switch to Thunderbolt input doesn't happen when the GPU is unsupported. What was the last version of macOS that you tried? I think I had an issue with Catalina but Monterey worked ok.

That was my understanding (the unsupported GPU blocks TB input.) I tried Big Sur and Catalina, rolling back to Mojave when it failed. Now I have better displays for my prime Mac, and a better system to use as server, so no need to try any more.

 

[Amethyst1]

I recently added a CalDigit Thunderbolt Station to my arsenal of TB toys, and if it weren't missing FireWire, this would be a full replacement for the Belkin TB1 dock. The following tests were carried out using my Late 2013 base 15" Retina MacBook Pro for native USB 3.0 and a freshly erased Samsung T5 SSD to eliminate my SATA-to-USB enclosure as (one of) the bottleneck(s) my previous results were subject to.

Native: the numbers to aim for.

Belkin (Fresco Logic FL1100 @ PCIe 1.0 ×1): the PCIe bottleneck rears its ugly head (but still 50% better than before!).

CalDigit (Fresco Logic FL1100 @ PCIe 2.0 ×1): still ≈17% short of the benchmark.

 

[joevt]

CalDigit (Fresco Logic FL1100 @ PCIe 2.0 ×1): still ≈17% short of the benchmark.

Yup. You need PCIe 3.0 x1 or 2.0 x2 or 1.0 x4 to get full USB 5Gb/s numbers but PCIe 2.0 x1 or PCIe 1.0 x2 is close enough for most people and maybe costs less.

 

[ToniCH]

I recently added a CalDigit Thunderbolt Station to my arsenal of TB toys, and if it weren't missing FireWire, this would be a full replacement for the Belkin TB1 dock. The following tests were carried out using my Late 2013 base 15" Retina MacBook Pro for native USB 3.0 and a freshly erased Samsung T5 SSD to eliminate my SATA-to-USB enclosure as (one of) the bottleneck(s) my previous results were subject to.

Here is a quick comparison of mine. MBP mid 2014 and Samsung 970 EVO Plus in Inateck USB-case. Don't know if it in any way relates to your results but anyways.

First natively plugged directly to the MBP:

And then into the Blackmagic RX580 TB3 eGPU which also has 4 USB-ports in the back so a kind of a TB dock

This is quite good! 👍

And then to make this little about iMac 2011 the same drive plugged to the Elgato Thuderbolt Dock 2 which is connected to my iMac 27" 2011 via TB:

Don't know if the test methods between these 2 benchmark sw produce comparable results but if they do it seems like the USB in your Caldigit is a bit more efficient than the Elgatos.

 

[Amethyst1]

[…] Samsung 970 EVO Plus in Inateck USB-case.

And then into the Blackmagic RX580 TB3 eGPU which also has 4 USB-ports in the back so a kind of a TB dock

Try plugging it into the eGPU’s second TB3 port: this should be 10 Gbps USB 3.1 Gen 2.

 

[ToniCH]

Try plugging it into the eGPU’s second TB3 port: this should be 10 Gbps USB 3.1 Gen 2.

Thanks for that! I didn't know I could plug USB-drives there!

So, I swapped the cable from USB-C - USB-A to TB3 cable and...

PS. this is the MBP 2014

 

[ToniCH]

And then...tadaa! The iMac 2011 27".

1. tried to plug the Inateck FE2025 -USB case with Apple Thunderbolt cable and TB2-TB3 adapter directly to the Elgato TB dock 2. Doesn't work. Power led on Inateck does not light up.

2. then I connected the eGPU to the Elgato TB dock 2 using the Apple adapter and the Inateck USB case again to the eGPU's second TB3 port. Had to use Apple 2m TB2 cable due distance. This combo works without any drivers so the eGPU works as a fast hub for the iMac (doesn't work as eGPU though)! Thanks for the tip Amethyst1, this was new to me! 👍

Here are the results:

So, now I know what to use if/when I need decently fast transfer route for external USB-drives and iMac. I need to investigate how my other USB 3.x cases work with this or do they work at all.

 

[Amethyst1]

1. tried to plug the Inateck FE2025 -USB case with Apple Thunderbolt cable and TB2-TB3 adapter directly to the Elgato TB dock 2. Doesn't work.

TB1/TB2 doesn’t natively carry USB. That came with TB3.

2. then I connected the eGPU to the Elgato TB dock 2 using the Apple adapter and the Inateck USB case again to the eGPU's second TB3 port.

You can connect the eGPU directly. But I guess the TB2 dock is your one-cable-to-connect-everything solution?

Thanks for the tip Amethyst1, this was new to me! 👍

Don’t thank me.

 

[ToniCH]

TB1/TB2 doesn’t natively carry USB. That came with TB3.

Roger 👍 So, with a Apple TB2-3 adapter I could use the Elgato TB Dock 3 with the iMac and plug the USB-drives directly to its second TB3 port?

You can connect the eGPU directly. But I guess the TB2 dock is your one-cable-to-connect-everything solution?

Well, trying to be. I still have some other, non speed critical stuff connected directly to the iMac like the USB audio out. Sure now that you say it, yes I could plug the eGPU direct to the iMac too for the data transfer.

BTW. I read that length of the TB cable affects transfer speeds and thus short ones are preferred in eGPU use. Is this true and have you observed difference in eGPU or data transfer speeds?

Don’t thank me.

Well, thanks to everybody for bringing knowledge of these cool things to others!

 

[Amethyst1]

Roger 👍 So, with a Apple TB2-3 adapter I could use the Elgato TB Dock 3 with the iMac and plug the USB-drives directly to its second TB3 port?

Yup. Any TB3 device with a second TB3 port will do.

 

[joevt]

1. tried to plug the Inateck FE2025 -USB case with Apple Thunderbolt cable and TB2-TB3 adapter directly to the Elgato TB dock 2. Doesn't work. Power led on Inateck does not light up.

Apple Thunderbolt 3 to Thunderbolt 2 Adapter is only for connecting Thunderbolt devices. The Inateck FE2025 is a USB device.
Also, Thunderbolt 2 doesn't have enough power for Thunderbolt 3 devices.
Thunderbolt 2 has enough power for the Apple Thunderbolt 1 to FireWire adapter and the Apple Thunderbolt 1 to Gigabit Ethernet Adapter and maybe some other Thunderbolt 2 bus powered devices.

And then...tadaa! The iMac 2011 27".
...
2. then I connected the eGPU to the Elgato TB dock 2 using the Apple adapter and the Inateck USB case again to the eGPU's second TB3 port. Had to use Apple 2m TB2 cable due distance. This combo works without any drivers so the eGPU works as a fast hub for the iMac (doesn't work as eGPU though)! Thanks for the tip Amethyst1, this was new to me! 👍

Your MBP mid 2014 supports Thunderbolt 2 (20 Gbps) so it is able to get full USB 10 Gbps from the eGPU.

Your iMac 2011 supports Thunderbolt 1 (10 Gbps) so it is only able to get near USB 10 Gbps from the eGPU. You might get a slight speed bump if the eGPU is connected directly to the iMac 2011?

To get the eGPU to work as a eGPU with a Thunderbolt 1/2 Mac, visit eGPU.io website for info.

BTW. I read that length of the TB cable affects transfer speeds and thus short ones are preferred in eGPU use. Is this true and have you observed difference in eGPU or data transfer speeds?

I don't think the length matters that much. The number of Thunderbolt devices between the host Mac and the device matters much more.

 

[ToniCH]

The Inateck FE2025 is a USB device.

Yes, I know. That is why I was so surprised that it worked so well in the TB3 connector. I am no more as I now better understand why it works. Thanks for that.

Prior to this I thought I need to have a specific TB hard drive case to use the TB bus. I knew new machines support both USB and TB3 in same connector but assumed there are separate circuits handling the 2 signals, didn't realize that the TB3 that actually supports USB by itself.

Your MBP mid 2014 supports Thunderbolt 2 (20 Gbps) so it is able to get full USB 10 Gbps from the eGPU.

Your iMac 2011 supports Thunderbolt 1 (10 Gbps) so it is only able to get near USB 10 Gbps from the eGPU. You might get a slight speed bump if the eGPU is connected directly to the iMac 2011?

To get the eGPU to work as a eGPU with a Thunderbolt 1/2 Mac, visit eGPU.io website for info.

Yes, I know that too. I need to give it a try connecting it directly and seeing if the dock slows things down on route.

I have my eGPU's working with many of my TB 1/2 machines with no problem. The only machine I have problems is the iMac 2011. The machine will not boot with Kryptonite installed. So, with the iMac I can use it as a fast USB/TB hub/switch but not as a eGPU. We have a thread about eGPUs in the first page of this section where these are discussed.

 

[ToniCH]

Your iMac 2011 supports Thunderbolt 1 (10 Gbps) so it is only able to get near USB 10 Gbps from the eGPU. You might get a slight speed bump if the eGPU is connected directly to the iMac 2011?

Allright - so, now this is tested. The Elgato TB Dock 2 does indeed limit transfer speed compared to directly connecting the eGPU to the iMac 27" 2011.

Here is the result for direct connection (compare to post #42):

So, in write speed we get only about 13MB/s better result but on read speed side we are seeing a significant 132MB/s improvement! 👍

 

[Amethyst1]

The Elgato TB Dock 2 does indeed limit transfer speed compared to directly connecting the eGPU to the iMac 27" 2011.

That’s curious. Okay, what about daisy-chaining multiple TB1/TB2 docks and attaching the eGPU and SSD to the end of that chain? 🤣

Here is the result for direct connection (compare to post #42):

I was able to hit 900 MB/s reading from a Samsung SM951 directly on TB1.

 

[ToniCH]

That’s curious. Okay, what about daisy-chaining multiple TB1/TB2 docks and attaching the eGPU and SSD to the end of that chain? 🤣

Nope.

I was able to hit 900 MB/s reading from a Samsung SM951 directly on TB1.

You have an actual TB case, my NVMe-drive is still in a USB case. The drive itself is capable to almost 3000MB/s in different setup of mine so I guess it might be the USB that slows it down here. Maybe TB case would be faster in my situation too? Well, that is the best I can do with the iMac 2011 and existing gear.