Enclosure & Hardware Discussions
TB3 Active cable performance

TB3 Active cable performance  


Eminent Member
Joined: 7 months ago

Hey guys, I have a question that has been digging through my brain for quite a bit. Is there any performance degradation when you use a long TB3 Active cable (2m) vs a short passive one? (50cm). I'm asking because the way my setup is laid out I really need the 2m cable, but I'm not sure if I'm being penalized for it...

MacBook Pro Touch Bar 2017 15" + Mantiz Venus MZ-02 + AMD Radeon Vega 64

Trusted Member
Joined: 9 months ago

I can give it a try tonight or tomorrow. I've been using a short passive cable with the Razer core X on my desk. I have a 2m active cable on hand. It would be nice to reclaim some desk space!

MBP 2018 15 inch + 2X Aorus gaming box 1080 in BootCamp and MacOS 10.13.6
2011 13-inch MacBook Pro + Razer Core X@10Gbps-TB1 (Zotac RTX 2080 Ti Amp) + Ubuntu 18.04

Eminent Member
Joined: 1 year ago

I don't think there is a difference. You can always buy it and do some benchmarks, return it if there's a large dip. Frankly I'd probably just use it and see if you NOTICE anything. Benchmarks are good for comparisons, but it's really more important how you feel using it.

LG Gram 17 | Sonnet Breakaway Box 550 | Asus Strix RTX 2070 OC Edition | Win 10 Pro 1903 + Manjaro Deepin Dual Boot
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Reputable Member
Joined: 2 years ago

I don't think cable length matters. Speed of electricity is very fast. an extra 1.5m will add up to a handful of micro seconds to the time it takes for a bit to reach the other end. This is not a problem because many bits are sent before expecting a reply.

Problems can arise if the extra length adds errors but the active part of the cable handles that.


Drop in performance happens when you chain multiple Thunderbolt 3 devices together.

Pending: Add my system information and expected eGPU configuration to my signature to give context to my posts

Noble Member Admin
Joined: 3 years ago

Noble Member Moderator
Joined: 2 years ago

Bandwidth would not be an issue between active vs. passive. I'm interested in seeing latency differences.

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2018 MacBook Pro 15" RP560X + Vega 64 [Sonnet Breakaway 350 -> 600W]