Labthrift Labthrift Buy the boring upgrade. Skip the rest.

Notes / Closet adjacent

Editorial, 22 Aug 2026. Specs from maker pages and recent street reports. We have not burned these units in. Affiliate tags are not live.

When 2.5G is full: the 10G copper card that ships a Cat6A lead

SFP+ is cheaper per port if both ends already have cages. If the NAS is 10GBASE-T and the desktop has a slot, TX401 is the one-SKU copper upgrade: 10/5/2.5/1G autoneg and a Cat6A in the box.

Still a later buy. Still not a switch. Stay on 2.5G copper until a single flow is full. If both ends have cages, buy the new 10Gtek 82599 plus a 2 m DAC instead. If the included 1.5 m is too short, add Monoprice / Cable Matters Cat6A.

The short list

CardWhat it isStreet, 22 Aug 2026Buy if
TP-Link TX401ASIN B08D71PVXG, UPC 840030701610. PCIe 3.0, low-profile bracket in box, 1.5 m Cat6A included. 10/5/2.5/1G autoneg.Amazon $64.50–$89.99 depending on capture. Sold by Amazon on the $89.99 snapshot. Recheck the live buy box.2.5G is actually full and the other end is RJ45. One SKU, no optic lottery.

Skip

Skip buying TX401 as your first NIC. Skip treating it as a switch. Skip used eBay 10GBASE-T pulls when this card is on a live Amazon ASIN.

Sources

Amazon TX401 ($64.50 / $89.99 captures). Same listing: amazon.com/dp/B08D71PVXG. SpeedTestHQ 2026 2.5G vs 10G cited a ~$50–$80 band — treat that as secondary to the live Amazon captures.

Also in this lane

USB vs PCIe 2.5G NIC for a 1G mini PCA $20–$30 adapter is the cheapest way to meet a 2.5G closet switch. SFP+ DAC cables for a closet 10G hopA 0.5–2 m passive DAC is the cheapest 10G link in the closet. Cat6a vs Cat5e in a closet that already does 2.5G2.5GBASE-T is specified to run on existing Cat5e. Do not rip walls.