Server Network Adapters Wholesale

How to choose a server network adapter

Size for the fabric you are growing into, not the one you have: 10/25 GbE for general nodes, 100/200 GbE with RoCE v2 for AI and HPC east-west traffic. ConnectX-5 and later speak RoCE v2; Intel E810 speaks both iWARP and RoCE — pick the family your switches and storage stack already run, and check SR-IOV support if you virtualise.

Match form factor and connector: OCP 3.0 SFF and standard PCIe cards are not mechanically interchangeable, so confirm the cage or riser against your chassis. QSFP56 ports accept QSFP28 optics at reduced rate — useful when migrating switch generations.

A 400G NDR card needs a PCIe 5.0 x16 host slot to reach line rate; in a PCIe 4.0 slot it trains down. The 200G dual-port variants remain the workhorse for mixed virtualisation and storage fabrics.

Budget the optics with the card — transceivers, AOC or DAC are the weak link in most bundles. We kit matched, coded optics and pre-verify them with the card at rated speed; specify reach and connector types in your BOM and they arrive plug-compatible.

Tell us the workload, switch generation and host platform — we will spec the exact variant, optics and cabling before quoting, and confirm the offload licence state on used stock.

NIC condition grades: new vs pulled vs refurbished

New adapters ship sealed with vendor support eligibility — specify new where firmware support contracts matter, or where your end customer audits the supply chain.

Pulled & tested cards are firmware-checked, unified per batch, and loopback-tested at rated speed with the result attached to the batch report; offload licence state is verified on used ConnectX parts. Optics are the weak link in most used bundles — ours are re-tested or replaced with new coded modules and pre-verified with the card. Bracket height is confirmed per batch, because low-profile and full-height cards arrive mixed in recycled stock.

Refurbished NICs barely exist as a distinct grade — most "refurbished" listings are pulls with cleaned housings — so judge the loopback report and the optics, not the label. A card that cannot show a rated-speed loopback result has not been tested at all.

NICs have no wear-out mechanics, so a verified pull is a low-risk saving at typically 30–50% below new. Both families — ConnectX and E810 — handle 25G and 100G with SR-IOV, PXE and iSCSI boot regardless of grade, so a mixed-grade BOM carries no compatibility penalty.