2x Thunderbolt 2 to Thunderbolt 3 Adapter

Dilster3k

macrumors 6502a
Original poster
Jul 20, 2014
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This may be a silly question, but I'm currently rocking a Retina MacBook Pro with 2x Thunderbolt 2 ports but don't want to miss out on the fun of Thunderbolt 3 (eGPU's, etc.)

So is it hypothetically possible to create an adapter that connects into both TB2 ports and comes out as one single TB3 port?
 

MCAsan

macrumors 601
Jul 9, 2012
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Atlanta
So two DP ports running TB2, USB 3, ...etc on one side and on the other side a USB-C port doing TB3, USB 3.1 high speed,...etc. I doubt it is possible for the average person. Can a lab do it on a big budget....very likely.

It will be very interesting to see how all the 3rd party TB docking station vendors deal with TB3 over USB-C. Maybe at least one of them may do the TB2-TB3 conversion in one of the products after the new Skylake machines are launched.
 

Dilster3k

macrumors 6502a
Original poster
Jul 20, 2014
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I'm aware it won't have all the functionality, like the same power throughput. But is it even possible at all?

Would love to use older devices with new upcoming Thunderbolt 3 displays.
 

MRxROBOT

macrumors 6502
Apr 14, 2016
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1011100110
Not likely to happen. I'm happy thunderbolt 3 seems to be off to such great start already, bums me out that thunderbolt 2 never really took off in regards to portable accessories. I make use of my ports but I wish more portable devices took advantage of the throughput.
 
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g4cube

macrumors 6502a
Apr 22, 2003
760
13
Things will get pretty complicated.

For computers that have a Thunderbolt 3 port, like the several HP, Lenovo, and Dell laptops and computers that have been released over the past several months, they are only compatible with Thunderbolt 3 or USB 3.1 peripherals that connect using Type-C cables.

To connect to older Thunderbolt 2 or 1 devices requires an adapter; and this adapter is only single direction. The adapters are announced, but are not shipping.

The opposite direction is probably not feasible at all: that is connecting an existing Thunderbolt 2 or 1 computer port to a new Thunderbolt 3 peripheral. QUite a complex thing to do. Intel originally had plans to produce a bidirectional adapter, but I understand that is no longer in the works due to the technical challenges making it not only difficult, but very expensive.

A lot still needs to happen.

Perhaps that is why LaCie put USB 3.1 as well as Thunderbolt 3 ports on its new 12big announced at NAB, using the USB 3.0 capability of USB 3.1 for backwards compatibility.
 

dyn

macrumors 68030
Aug 8, 2009
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It's not a matter of physical connections, it is a matter of the protocol itself. TB3 is backwards compatible with TB2 but TB2 isn't forward compatible with TB3. Whatever you do, TB2 will not support TB3 specific features such as the eGPU.

You want all features of TB3? Then the only solution is to buy a computer with TB3. There are no other solutions, hacks, workarounds, fairy dusts, etc. possible.
 

Brian33

macrumors 6502a
Apr 30, 2008
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USA (Virginia)
OK, I certainly don't know the details of the Thunderbolt protocols, but I'd be surprised if it were that difficult or expensive to make a "smart" adapter that would allow TB2 computer use a TB3 device (for example, a disk drive array, let's say). It's all digital signal; I agree with the poster "boast", above. Of course in that scenario, you can't get 40 Gbps TB3 "speeds" from a 20 Gbps TB2 port on the computer...

...but, IF making such an adapter were feasible, then perhaps, as the original poster suggested, the throughput (to the adapter) could be boosted by using two TB2 ports on the computer. isn't there something similar already done to allow two DisplayPort ports drive a super high-res display, one that would normally require more throughput than one DisplayPort could provide?
 

dyn

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Aug 8, 2009
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There will be some loss in overhead, but I don't see why an FPGA cannot be programmed to transcode between TB2 and TB3.
There will be loss of functionality because TB2 doesn't support USB3.1 nor eGPU and other TB3 specific features. How would you transcode something to something that doesn't exist?
 

g4cube

macrumors 6502a
Apr 22, 2003
760
13
There will be loss of functionality because TB2 doesn't support USB3.1 nor eGPU and other TB3 specific features. How would you transcode something to something that doesn't exist?
There will be loss of functionality because TB2 doesn't support USB3.1 nor eGPU and other TB3 specific features. How would you transcode something to something that doesn't exist?
Also, there is no FPGA technology that is fast enough. Yes, you may think it's "all digital", but it's a lot more than even the most advanced FPGA can handle.
 

Dilster3k

macrumors 6502a
Original poster
Jul 20, 2014
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Obviously the older ports won't be able to pass power to lets say a new MacBook. But maybe being able to communicate with TB3 monitors or eGPUs would be great because it does hit 40 Gbps together.
 

dyn

macrumors 68030
Aug 8, 2009
2,708
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.nl
The displays most likely won't be an issue for things like output and usb. eGPU is a more difficult thing. With TB1 and 2 it was already possible to have an external videocard but it required some work and it doesn't work reliably. TB3 has official eGPU support meaning that the TB protocol itself is designed for it. Most likely it will address the issues that are there with TB1 and 2 but it remains to be seen if it will be compatible with TB1/2 computers.
 

g4cube

macrumors 6502a
Apr 22, 2003
760
13
One other thing to consider with any adapter, each Thunderbolt 3 port must provide 15watts of power. Not optional. Required.
 

Dilster3k

macrumors 6502a
Original poster
Jul 20, 2014
790
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One other thing to consider with any adapter, each Thunderbolt 3 port must provide 15watts of power. Not optional. Required.
I guess we'll have to say farewell to TB1/2 and move onto 3 just to be ditched by 4 in the years to come.
 
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