This article covers StarTech.com 10Gbイーサネットx2増設PCIe対応LANカード ST20000SPEXI.

Overview

The StarTech.com ST20000SPEXI is a dual-port 10GBASE-T network card that fits into a single PCI Express slot. Powered by the Intel X540 chipset, each RJ45 port delivers up to 10Gbps in full-duplex mode, for a combined bandwidth of 20Gbps. It's a cost-effective way to add high-speed 10GbE connectivity to a workstation or server without breaking the bank. This card uses a PCI Express 2.0 x8 interface and ships with both full-profile and low-profile brackets, making it compatible with a wide range of desktop and server chassis. It also supports PXE network boot and Intel Virtualization Technology (VT), so it's ready for business environments and home labs alike.

Connectivity & Compatibility

Interface: PCI Express 2.0 x8 (requires an x8 or larger slot) Network standards: IEEE 802.3 / 802.3u / 802.3ab (10GBASE-T, 1000BASE-T, 100BASE-TX) OS support: Windows, Linux, macOS, and others Brackets included: Full-profile (pre-installed) + low-profile bracket * Supported features: VLAN tagging, jumbo frames, Auto-MDIX, PXE boot, Intel VT

Product Info

Released around 2015, the ST20000SPEXI remains a popular choice for adding 10GbE on a budget. Pricing hovers around ¥49,000 (~$340) on Japan as of June 2026. The card comes with a 2-year manufacturer warranty and free lifetime technical support. In the box you get the NIC, a low-profile bracket, and a quick-install guide. Market positioning is mid-range to high-end. It's more affordable than many enterprise-grade 10GbE adapters, yet uses the reliable Intel X540 controller. This makes it a solid middle ground for users who want genuine 10GbE performance without paying top dollar for the latest chipset.

Best Use Cases

NAS and file-server owners: Upgrading to 10GbE dramatically speeds up large file transfers and backups. If your current 1GbE link is a bottleneck, this card will unlock your storage's full potential. Just remember you'll also need a 10GbE switch and Cat6A cabling. Home lab and small-office admins: The dual-port design allows link aggregation or failover configurations. Intel's chipset provides the stability expected in business environments. It's a great fit for anyone building a cost-effective 10GbE network. * Video editors and 3D artists handling large project files: Moving multi-gigabyte assets between workstations becomes much faster with 10GbE. However, this card requires a free PCIe x8 slot, so it won't work in compact PCs or laptops.

Things to Consider

This card requires a PCI Express 2.0 x8 slot (or higher). Plugging it into an x4 slot will limit bandwidth and prevent full 10Gbps performance. On PCIe 3.0 or newer slots, x4 lanes may be sufficient, but StarTech officially recommends x8 or greater. Building a full 10GbE setup also means investing in a compatible switch and Cat6A (or better) cabling. Factor in those costs before buying. The card itself generates moderate heat, so good case airflow is recommended. Alternatives include the ASUS XG-C100C (single-port, PCIe 3.0 x4) and StarTech's own single-port ST10GSPEX. If you only need one 10GbE port, those are cheaper options. Choose the ST20000SPEXI if you genuinely need two ports for redundancy or link aggregation.

Product Disclosure (Amazon)

  • Manufacturer: StarTech.com(スターテック)
  • Seller: Amazon US
  • Fulfilled by: Amazon US
  • ASIN: B015HDT6AY
  • Note: This article covers a manufacturer-made product based on Amazon listing details.