Cisco Copper Cable - 100GBase direct attach cable - QSFP (M) to QSFP (M) - 3 m - passive - for Mellanox ConnectX-5 Ex EN, Nexus 93108TC-EX, 93180YC-FX, 9336C-FX2

Product Overview

AI-generated summary

At £109.21 ex-VAT for a 3m passive QSFP direct-attach, this is the kind of cable that’s worth it only if you’re confident you’re buying the *right* brand/compatibility lane. With ConnectX-5 and those Nexus models you listed, it should slot in cleanly, but the real-world headache with passive DACs is always “will the switch and optics expect the same electrical behavior and vendor ID?” If you’ve already proven these exact Cisco-branded DACs work in your environment, then yes—good value compared to buying optics plus transceivers. You get plug-and-go simplicity and you avoid the higher per-port cost of active optics.

That said, I’d be cautious if you’re trying to generalise this beyond those specific platforms or if you’ll be mixing vendors/transceivers in the same fabric. Passive DACs are less forgiving when link training or compatibility quirks show up, and troubleshooting can turn into a time sink (especially in production). So: buy it if you’re standardising those Nexus/ConnectX-5 links at ~3m and want predictable performance. Don’t buy it if you need flexibility across different switch families or link lengths—then you’re often better off with an active solution or a more broadly validated part, even if it costs more upfront.