USB-C to USB-A cable

[nabz0r Veteran]

I just borrowed a Lenovo USB-C Dock from a friend. I want to test if I could run my two 4k monitors, keyboard and ethernet through this docking station, BUT the problem is that the cable it connects the dock to the PC/Mac is a USB-C (which my older Mac late 2015 doesn't have), is there a way I could connect the dock to my Mac with USB-A instead? I mean if there is a cable that I could buy with both types i.e one end USB-C and the other USB-A? Or a female USB-C adapter to male USB-A?

[Nick H. Supervisor]

There are adapters out there, we've just installed Lenovo Hybrid docks that work for the T480s with USB-C but also come with an adapter for the older models that use USB-A. But I have no idea how well they work with Macs.

[nabz0r Veteran]

15 minutes ago, Nick H. said:

There are adapters out there, we've just installed Lenovo Hybrid docks that work for the T480s with USB-C but also come with an adapter for the older models that use USB-A. But I have no idea how well they work with Macs.

Can you post links to those adapters? I actually haven't find anything yet. These should work on Macs if you have DisplayLink drivers installed (not sure though, that's why I want to test it before I buy or never give back the dock to my friend :D)

[Nick H. Supervisor]

18 minutes ago, nabz0r said:

Can you post links to those adapters? I actually haven't find anything yet. These should work on Macs if you have DisplayLink drivers installed (not sure though, that's why I want to test it before I buy or never give back the dock to my friend :D)

https://www.distrelec.ch/de/adapter-usb-male-usb-female-exsys-ex-47991/p/30077742?channel=b2c&price_gs=7.539&source=googleps&ext_cid=shgooaqchde-blcss&kw={keyword}&gclid=CjwKCAiAwJTjBRBhEiwA56V7q_L4biQoiHEVwdrzUZEZse-R6ZzxAd1TcPDEISA7RpPK2t15gYrmMRoCnQ4QAvD_BwE

 

And I opened one of the docks to show that they exist in real life

 

[nabz0r Veteran]

Thanks. I've found this one and ordered it, hopefully I don't experience any glitch/flickering. 

Hehe, I know they exists, I've seen that docking station but it's expensive and I can't give a good reason to my boss to buy one for me.

[DevTech]

2 hours ago, nabz0r said:

Can you post links to those adapters? I actually haven't find anything yet. These should work on Macs if you have DisplayLink drivers installed (not sure though, that's why I want to test it before I buy or never give back the dock to my friend :D)

This sounds crazy.

 

USB 3.0 which uses the USB-A connector maxes out at 5 gbits

 

USB 3.1 Gen 2 uses the USB-C connector and maxes out at 10 gbits

 

Thunderbolt 3 uses the USB-C connector and maxes out at 40 gbits

 

Now, guess which one of those 3 is going to drive two 4K monitors?

 

 

[DevTech]

You  might have a Thunderbolt 2 connector at which point the ideal solution would be a Thunderbolt 2 dock. Only Macs used Thunderbolt 2, so any doc will be obviously Mac styled to distinguish it from the more modern Thunderbolt 3 docks which are used by PCs like the Dell XPS, Lenovos etc.

 

https://support.apple.com/en-ca/HT201736

 

 

Thunderbolt 3 (USB-C)

 

Use Thunderbolt 3 (USB-C)  with displays and other devices that connect using a Thunderbolt 3 (USB-C) cable or USB-C cable. You can also connect a USB-C power adapter and cable to charge your notebook computer. If you have a device that doesn't connect to this port, you might be able to use an adapter to connect it.

 

These Mac models have Thunderbolt 3 (USB-C) ports:

 

iMac Pro

iMac models from 2017

Mac mini (2018)

MacBook Pro models from 2016 or later

MacBook Air (Retina, 13-inch, 2018)
   

USB-C

 

Use USB-C  with displays and other devices that connect using a USB-C cable. You can also connect a USB-C power adapter and cable to charge your notebook computer. If you have a device that doesn't connect to this port, you might be able to use an adapter to connect it.

 

MacBook models from 2015 and later have a USB-C port. This port doesn't support Thunderbolt devices.
   

USB-A

 

Use USB-A  with devices that connect using a USB cable. USB ports are sometimes known by the USB specification of the port: USB 3, USB 2, or USB 1. The USB specification relates to the speed at which the port can transfer data, and the amount of power it can supply to a connected device.
   

Thunderbolt 2, Thunderbolt

 

Use Thunderbolt 2  or Thunderbolt  with displays and other devices that connect using a Thunderbolt cable. 

Thunderbolt 2 and Thunderbolt are not the same as Mini DisplayPort . They have the same shape, but use different symbols on the cable and port.
   

Mini DisplayPort

 

Use Mini DisplayPort  with displays that connect using a Mini DisplayPort cable.

Mini DisplayPort is not the same as Thunderbolt 2 or Thunderbolt . They have the same shape, but use different symbols on the cable and port.
  

HDMI

 

Use HDMI with displays and TVs that connect using an HDMI cable.

 

 

 

 

 

 

 

[goretsky Supervisor]

Hello,

 

From looking at the Lenovo ThinkPad USB-C Dock User Guide, you would connect the dock to the 2015 Apple Mac by plugging a certified USB 3.1 gen 2 cable between them.  One end of the cable goes to the 2015 Apple Mac's USB 3.0 Type-A connector, and the other end to the dock's USB 3.1 gen 2 Type-C connector next to the Lenovo Slim Tip power connector.  Here are a couple of examples of the type of cable you can use:  Amazon, Monoprice.  I am not specifically recommending those cables, just giving them as examples of the type you need.

 

Note that you may still need drivers to access all of the dock's features, which is something Lenovo does not provide for macOS.  They may be available from Apple or other sources, though.

 

I would specifically suggest that you avoid using any kind of adapter with the existing Lenovo-provided Type-C cable, as there is no guarantee the adapter passes the correct signals through it.  Also, some of the Lenovo ThinkPad USB-C dock's features may not work if they rely on USB-C Alternate Modes unsupported on the 2015 Apple Mac.

 

Regards,

 

Aryeh Goretsky

[DevTech]

11 minutes ago, goretsky said:

Hello,

 

From looking at the Lenovo ThinkPad USB-C Dock User Guide, you would connect the dock to the 2015 Apple Mac by plugging a certified USB 3.1 gen 2 cable between them.  One end of the cable goes to the 2015 Apple Mac's USB 3.0 Type-A connector, and the other end to the dock's USB 3.1 gen 2 Type-C connector next to the Lenovo Slim Tip power connector.  Here are a couple of examples of the type of cable you can use:  Amazon, Monoprice.  I am not specifically recommending those cables, just giving them as examples of the type you need.

 

Note that you may still need drivers to access all of the dock's features, which is something Lenovo does not provide for macOS.  They may be available from Apple or other sources, though.

 

I would specifically suggest that you avoid using any kind of adapter with the existing Lenovo-provided Type-C cable, as there is no guarantee the adapter passes the correct signals through it.  Also, some of the Lenovo ThinkPad USB-C dock's features may not work if they rely on USB-C Alternate Modes unsupported on the 2015 Apple Mac.

 

Regards,

 

Aryeh Goretsky

Do you honestly think he is going to drive his 2 4K monitors off a 5 gbits USB 3.0 USB-A signal?

 

[goretsky Supervisor]

Hello,

 

Yes,  Not at their full 4K-resolution, of course, but something like FHD (1920x1080) should be attainable, at least as long as there is no contention on the USB bus from things like external drives, network adapters and the like.  I have run a 1600x1200 display using a USB 3.0 adapter on even older hardware (2013-era ThinkPad), and it worked well enough for using Microsoft Office, watching videos, etc., as long as I didn't access any of my external USB drives.

 

Regards,

Aryeh Goretsky

 

21 minutes ago, DevTech said:

Do you honestly think he is going to drive his 2 4K monitors off a 5 gbits USB 3.0 USB-A signal?

 

 

[DevTech]

15 hours ago, nabz0r said:

run my two 4k monitors, keyboard and ethernet through this docking station

 

55 minutes ago, goretsky said:

  I have run a 1600x1200 display using a USB 3.0 adapter on even older hardware (2013-era ThinkPad), and it worked well enough for using Microsoft Office, watching videos, etc., as long as I didn't access any of my external USB drives.

 

Here is a handy calculator so you can try different scenarios:

 

https://www.extron.com/product/videotools.aspx

 

 

---------------------------

 

Assuming professional usage and not gaming, 60 hz should be a workable refresh.

 

If we go a bit underneath 4K to the common 3840 x 2160 resolution and assume good color rendition at 10 bits and full 4:4:4 Chroma, then we get:

 

22.38 gbits per monitor = 45 gbits required bandwidth

 

That requires full on Thunderbolt 3 to even have a chance of working!

 

If we consider 2 monitors down-sized to 1920 x 1080 and down-colored to 8 bits we get 4.5 gbits per monitor for a total of 9 gbits for the 2 monitors.

 

That could (barely) be handled by USB 3.1 USB-C with it's 10 gbits...

 

With USB 3.0, you need lots of imagination to picture yourself in the fond memories of the 1990's and you just walked out of the movie theater after watching Hackers (https://www.imdb.com/title/tt0113243/) and you really want to recreate those low res CRT screens for your daily productivity - after all, it works in preventing terrorists from taking over oil tankers, right?

 

-------------------------

 

Some additional background info:

 

http://www.acousticfrontiers.com/uhd-101-v2/

 

"Great article! I have finally some answers to the question that I had: “Is 18 Gbps enough to carry 4K 60fps 4:4:4 with a 10-bit color depth?. Unfortunately, if I read you well, the answer is no. I must say it is somewhat disappointing"

 

 

[nabz0r Veteran]

Thank you @DevTech and @goretsky for the detailed posts, much appreciated. If this dock doesn't work (which it might not) do you have any other suggestions for a dock that  supports two 4k monitors, ethernet, etc for Mac? I don't really care if it uses Minidisplay,, USB or thunderbolt. Today I am using both thunderbolt ports for my monitors, both USB ports one for my keyboard and the other one is for ethernet and it works great but sometime I need a USB port so a dock would be nice to avoid the use of all ports.

[Brandon H Supervisor]

4 hours ago, nabz0r said:

Thank you @DevTech and @goretsky for the detailed posts, much appreciated. If this dock doesn't work (which it might not) do you have any other suggestions for a dock that  supports two 4k monitors, ethernet, etc for Mac? I don't really care if it uses Minidisplay,, USB or thunderbolt. Today I am using both thunderbolt ports for my monitors, both USB ports one for my keyboard and the other one is for ethernet and it works great but sometime I need a USB port so a dock would be nice to avoid the use of all ports.

from the sound of your setup I think you may be better off just getting a USB Hub to give you some extra ports rather then messing with a (likely) more expensive dock that may or may not give you your full resolution or work at all.

 

just my 2 cents for you

[DevTech]

1 hour ago, Brandon H said:

from the sound of your setup I think you may be better off just getting a USB Hub to give you some extra ports rather then messing with a (likely) more expensive dock that may or may not give you your full resolution or work at all.

 

just my 2 cents for you

Oh yeah, that's the answer!

 

Messing around with TWO 22 gbit bandwidth signals is already close to magic just to get good solid cables to the monitors. Running that through the delay and extra cables etc of a DOck is just asking for the Glitchyness Monster

[goretsky Supervisor]

Hello,

What is the exact model of 2015 Apple Mac you are using?  There were various MacBook Pros, plus a MacBook Air, released that year.

 

Regards,

 

Aryeh Goretsky

 

9 hours ago, nabz0r said:

Thank you @DevTech and @goretsky for the detailed posts, much appreciated. If this dock doesn't work (which it might not) do you have any other suggestions for a dock that  supports two 4k monitors, ethernet, etc for Mac? I don't really care if it uses Minidisplay,, USB or thunderbolt. Today I am using both thunderbolt ports for my monitors, both USB ports one for my keyboard and the other one is for ethernet and it works great but sometime I need a USB port so a dock would be nice to avoid the use of all ports.

 

[DevTech]

On 2/15/2019 at 9:47 AM, nabz0r said:

Thank you @DevTech and @goretsky for the detailed posts, much appreciated. If this dock doesn't work (which it might not) do you have any other suggestions for a dock that  supports two 4k monitors, ethernet, etc for Mac? I don't really care if it uses Minidisplay,, USB or thunderbolt. Today I am using both thunderbolt ports for my monitors, both USB ports one for my keyboard and the other one is for ethernet and it works great but sometime I need a USB port so a dock would be nice to avoid the use of all ports.

 

19 hours ago, goretsky said:

What is the exact model of 2015 Apple Mac you are using?  There were various MacBook Pros, plus a MacBook Air, released that year.

 

 

From https://support.apple.com/en-ca/HT201736 we know that he does not have Thunderbolt 3.

 

MacBook Pro from 2016 and later has two Thunderbolt 3 (USB-C) ports on each side

 

From his post we know he has TWO Thunderbolt 2 ports.

 

MacBook Pro (Retina, 15-inch, Mid 2015) has power, two Thunderbolt 2, USB-A, and Audio-out on the left side

 

Each Thunderbolt 2 port is 20 gbits which is exactly what is needed for 4K that is limited to 60 hz

 

He needs to just buy a simple (or fancy) USB 3.0 HUB to extend his low speed peripheral ports.

 

He has limited bandwidth left over to drive any kind of external storage (with decent performance) since no matter how you look at it, he is constantly pumping out 40 gbits to drive the 2 external 4K monitors.

 

 

 

"If this dock doesn't work (which it might not) "

 

It will NOT work. Don't waste your time.

 

 

 

 

"do you have any other suggestions for a dock that  supports two 4k monitors, ethernet, etc for Mac? I don't really care if it uses Minidisplay,, USB or thunderbolt."

 

BUT YOU DO CARE! Unless you are a graduate of the X-Men Academy (or Donald Trump), you are constrained by the Laws of Physics.

 

You need a minimum of 40 gbits for any possible dock to do what you want.

 

 

 

1. MiniDisplayPort - you are confusing this with Thunderbolt 2 - Apple use a MiniDisplayPort connector for Thunderbolt 2 but Thunderbolt 2 pumps out 20 gbits over that connector, good for ONE 4K monitor.

 

 

 

2. USB - You are probably making an even larger Mental Mash-up of Confusion over USB-A, USB-C and Thunderbolt 3. Any USB-A port on your Mac (or any device) is ONLY good for 5 gbits which means you need to combine FOUR USB ports to get a single 20 gbits signal which wouldn't work anyways because internally 4 external USB-A ports will be sharing PCIe lanes from the chipset.

 

It sure as heck does not help that Thunderbolt 3 ended up using another easily confused common cable, USB-C to run it's high speed magic.

 

 

 

 

3. Thunderbolt 3 is what you care about, since that is what you 100% require in a dock scenario and you need a hypothetical dock that takes TWO Thunderbolt 2 cables (looks like MiniDisplayPort) as INPUT in order to drive TWO 4K monitors.

 

 

 

Also, it should be noted that the CABLE LENGTH of Thunderbolt 3 is limited to 1/2 meter (1.5 ft) or else the speed of Thunderbolt 3 goes from the REQUIRED 40 gbits to old Thunderbolt 2 speeds of 20 gbits.

 

To run a longer cable requires Active Circuits inside the cable to stabilize the very high data rate of 40 gbits.

 

 

REFERENCE INFO:

 

https://en.wikipedia.org/wiki/Thunderbolt_(interface)

 

https://support.apple.com/en-ca/HT201736

 

https://www.apple.com/thunderbolt/

 

https://www.datapro.net/techinfo/thunderbolt_info.html

 

https://www.bhphotovideo.com/explora/computers/tips-and-solutions/thunderbolt-3-usb-31-usb-type-c-making-sense-connections

 

 

 

[nabz0r Veteran]

Sorry guys for the late reply, been sick in the bed for the past 8 days and I am now better, thankfully.

 

@Brandon H, that is probably the best solution for me and I've been wondering for some time now to order this (i might probably end up with this, but I do need to test the stuff I ordered before I purchase this) and the ONLY reason I am looking for a dock is just to be able to only connect one cable to my Mac.

 

@goretsky, the exact model is MacBook Pro 11,4

 

@DevTech, Option one, is what my current setup is. I use two of these for my two monitors, and use one of the USBs to connect my ethernet and the other one is for my keyboard. I don't know why there is no dock specific to Mac computers.

[goretsky Supervisor]

Hello,

 

I could not find the "MacBook Pro 11,4" listed at https://everymac.com/systems/by_year/macs-released-in-2015.html.  Can you tell me which model from that page it is, or link to it if it is not listed?  Some of the computers Apple released in 2015 have Thunderbolt 2 ports, which have a 20Gbit/s of bandwidth.

 

Regards,

 

Aryeh Goretsky

 

[DevTech]

6 hours ago, goretsky said:

Hello,

 

I could not find the "MacBook Pro 11,4" listed at https://everymac.com/systems/by_year/macs-released-in-2015.html.  Can you tell me which model from that page it is, or link to it if it is not listed?  Some of the computers Apple released in 2015 have Thunderbolt 2 ports, which have a 20Gbit/s of bandwidth.

 

Regards,

 

Aryeh Goretsky

 

He already said his Mac had two Thunderbolt 2 ports which is is currently using for TWO 4K monitors.

 

Since a single 4K monitor uses a bit more than 20 gbits he is fully utilizing his bandwidth.

 

As I already mentioned, if some weird dock existed that is designed so he can plug in BOTH of his Thunderbolt 2 ports, then that dock could in turn connect to TWO 4K monitors in some cosmic act of pure silliness.

 

Since the entire objective turns out after much crazy talk in this thread to be just plugging in a few extra USB peripherals, ALL he needs is a PLAIN OLD USB HUB...

 

It is also hard to imagine that inside the laptop, there is practically enough I/O bandwidth to simultaneously pump out enough data that is switched from Video to PCIe lanes to feed a dock which then converts back to some sort of emulated 4K video...

 

It's an OLD laptop, not a MainFrame with dedicated I/O Channel Processors!

 

 

 

 

 

[DevTech]

On 2/23/2019 at 12:01 PM, nabz0r said:

 

@DevTech, Option one, is what my current setup is. I use two of these for my two monitors, and use one of the USBs to connect my ethernet and the other one is for my keyboard. I don't know why there is no dock specific to Mac computers.

Due to your illness, you obviously have not been reading what I have posted and the background info in the links I provided. "Stuff" happens...

 

From your description, I have figured out exactly what your are doing and have then tried to explain to you how that fits into the tech ecosystems.

 

I guess by pure luck you have a maxxed out your config which is "optimal" in terms of using all your I/O bandwidth. There is nothing left over to play with.

 

To achieve more in the crazy Mac Universe, you would need a desktop Mac Pro which has many more I/O ports to do all sorts of stuff.

 

A modern workstation class laptop from Lenovo, HP, Dell, and others would also have increased professional capacity.

 

Apple pioneered the Thunderbolt interface with Intel and there are actually tons of Mac specific docks and peripherals left over from those days. The vast majority of that ecosystem is Thunderbolt 2. Lots of docks, hard drivers and other devices exist in white or metal colors at some really nasty prices endemic to the Mac ecosystem. In the case of Thunderbolt, there was an added price "kicker" with Intel license fees since you need an Intel Thunderbolt chip at both ends of the cable.

 

The "Thunderbolt Industry/Ecosystem" has been hanging by a thread and the insane prices just got worse with Thunderbolt 3. Finally last year I think, Intel dropped the license fees to encourage adoption so maybe Thunderbolt 3 will have a chance. Is it too little, too late? I created a special thread here to track high speed interconnects inspired by your question and we'll see if anything such as Intel/Mellanox InfiniBand can  overtake Thunderbolt 3.

 

 

 

 

[goretsky Supervisor]

Hello,

 

I saw that, but I'd like to know more about the exact model of Apple Mac, as there may be other issues which need to be addressed.

 

Regards,

 

Aryeh Goretsky

 

 

12 hours ago, DevTech said:

He already said his Mac had two Thunderbolt 2 ports which is is currently using for TWO 4K monitors.

 

Since a single 4K monitor uses a bit more than 20 gbits he is fully utilizing his bandwidth.

 

As I already mentioned, if some weird dock existed that is designed so he can plug in BOTH of his Thunderbolt 2 ports, then that dock could in turn connect to TWO 4K monitors in some cosmic act of pure silliness.

 

Since the entire objective turns out after much crazy talk in this thread to be just plugging in a few extra USB peripherals, ALL he needs is a PLAIN OLD USB HUB...

 

It is also hard to imagine that inside the laptop, there is practically enough I/O bandwidth to simultaneously pump out enough data that is switched from Video to PCIe lanes to feed a dock which then converts back to some sort of emulated 4K video...

 

It's an OLD laptop, not a MainFrame with dedicated I/O Channel Processors!

 

 

 

 

 

 

[nabz0r Veteran]

@goretsky, I think this is the exact model: I7-4870HQ.

 

@DevTech, I've read your posts and I understand what you are saying. And I am going to purchase a usb-hub + rj45. 

[DevTech]

2 hours ago, goretsky said:

Hello,

 

I saw that, but I'd like to know more about the exact model of Apple Mac, as there may be other issues which need to be addressed.

 

Regards,

 

Aryeh Goretsky

 

 

 

Good idea. The other issues should certainly need to be resolved.

 

The exact model number could be quite helpful  in determining compatibility with the Lenovo dock, although it probably would work better if he exchanged his Mac for a Lenovo laptop unit which is bound to work better with a Lenovo dock, one might imagine. A Lenovo workstation with multiple Thunderbolt 3 ports would provide higher bandwidth.

 

 

[nabz0r Veteran]

31 minutes ago, DevTech said:

The exact model number could be quite helpful  in determining compatibility with the Lenovo dock, although it probably would work better if he exchanged his Mac for a Lenovo laptop unit which is bound to work better with a Lenovo dock, one might imagine. A Lenovo workstation with multiple Thunderbolt 3 ports would provide higher bandwidth.

I'd love to buy a Lenovo T480 but I don't think my boss would be so glad if I order one. I have only had this Mac since november 2017 and the reason I didn't order the newer Mac back then was/is/will be the touch bar.

[DevTech]

On 2/25/2019 at 4:17 AM, nabz0r said:

 

@DevTech, I've read your posts and I understand what you are saying. And I am going to purchase a usb-hub + rj45. 

That hub does not specify if Gigabit Ethernet or not.

 

Also, you should try hard to select a hub that has a large power adapter since a laptop will not provide the power to all peripherals as specified in the USB 3.0 spec.

 

The power brick for a quality USB 3.0 Hub will be as large as a laptop power supply.