StarTech.com Cisco QSFP-H40G-CU5M Compatible 5m 40G QSFP+ to QSFP+ Direct Attach Cable Twinax - 40GbE QSFP+ Copper DAC 40 Gbps Low Power Passive Transceiver Module DAC Firepower C9200 C9400

Product Overview

AI-generated summary

This is a pretty straightforward, no-drama DAC: passive twinax, 40GbE QSFP+ to QSFP+ at 5m, and it’s priced like a “fill-the-gap” cable rather than a premium Cisco-branded item. At ~£32 ex-VAT you’re getting decent value if you know your optics/copper requirements and the distance is bang on. For UK datacentres, 5m is a very common short-run use case—top-of-rack to switch, switch-to-switch in the same rack row—so long as your switches support 40G QSFP+ DACs and the port isn’t picky about compatibility.

Who should buy: teams standardising on QSFP+ 40GbE and wanting to keep costs down on short interconnects, especially for Firepower/Cisco 9000-series style environments where “it just has to work” matters more than fancy cables. Who should not: if you need longer reach, higher tolerance, or you’re unsure whether your exact model/port will handshake cleanly—DACs are usually fine, but incompatible transceivers/cables can waste time fast. If you’re buying this just because it’s cheap, make sure it’s truly within spec for your switch and cabling path; otherwise you’re better off paying a bit more for something you’ve already validated in your setup.