Macbook Pro 13" 2015 using the second thunderbolt port for a HDD
Clear all

Macbook Pro 13" 2015 using the second thunderbolt port for a HDD  


New Member
Joined: 11 months ago

Probably a quick question to answer but should I run an external hdd on the second thunderbolt port on the 2015 Macbook Pro 13" or is the bandwidth shared between the two ports? And is there any difference between Port 1 and Port 2?

Would I be better off just using a USB3 port? The drive I have is a LaCie which supports both.

I have the Blackmagic 580 using the apple TB3 > TB2 adapter and my experience so far has been really solid.

I'm only using MacOS currently and I use the eGPU for video editing, compositing, design, photogrammetry and 3D modelling related stuff with some light gaming.


To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.


rufus liked
Famed Member Moderator
Joined: 3 years ago

@pricicles, The bandwidth is shared (same controller). So experience will depend on a lot of factors and how often you read/write. Best to try and see. You can always revert to USB in case things aren't smooth.


Insights Into macOS Video Editing Performance

Master Threads:
2014 15-inch MacBook Pro 750M
2018 15-inch MacBook Pro

2019 13" MacBook Pro [8th,4C,U] + RX Vega 64 @ 32Gbps-TB3 (Mantiz Venus) + macOS 10.14.6 & Win10 [build link]