This article covers StarTech.com 2ポートUSB 3.0増設PCI Expressカード PEXUSB3S24.

Overview

The StarTech.com PEXUSB3S24 is a PCI Express interface card that adds two USB 3.0 ports to your desktop PC. It features an NEC controller chip with UASP (USB Attached SCSI Protocol) support, enabling faster data transfers compared to standard USB 3.0. With a maximum transfer rate of 5 Gbps, it is ideal for external SSDs or large file backups. This product targets users who need extra USB ports or want to improve the performance of built-in USB ports on older systems. A low-profile bracket is included, allowing installation in compact or slim cases.

Compatibility Guide

The PEXUSB3S24 complies with PCI Express 2.0 x1 and works in PCI Express x1/x4/x8/x16 slots. Supported operating systems include Windows 7/8/10/11, Linux, and macOS (some versions). The card supports both standard and low-profile form factors, with two brackets included. Power can be supplied via the PCIe slot alone, or optionally via a SATA power connector for up to 900mA per USB port. It supports USB Battery Charging Specification 1.2, allowing charging of smartphones and tablets.

Product Info

This card was originally released around 2014 and remains a popular, long-selling product. On , it is priced around ¥4,652 (tax included), offering excellent value. The manufacturer provides a 2-year warranty. Positioned at the entry-to-mid range, it is a reliable choice for users who need to add USB 3.0 ports without spending much. The NEC chip ensures stability, and UASP support delivers noticeably faster speeds, especially on older PCs with weak built-in USB controllers.

Best Use Cases

Ideal for users who need additional USB ports to connect multiple external HDDs or SSDs. If you use UASP-compatible external storage, you can fully utilize the 5 Gbps bandwidth. Great for older PCs (Intel 6th gen or earlier) where built-in USB 3.0 ports may be bottlenecked; this card provides a dedicated controller for better throughput. * Perfect for compact or slim case owners, thanks to the included low-profile bracket.

Things to Consider

This card uses PCI Express 2.0 x1, limiting maximum bandwidth to 5 Gbps. When using multiple devices simultaneously, bandwidth is shared, which may reduce individual speeds. It does not support USB 3.1 Gen2 (10 Gbps) or USB 3.2 Gen2x2 (20 Gbps), so it is not suitable for high-speed NVMe external SSDs that require faster interfaces. Without the optional SATA power connector, the power delivered to each USB port may be less than 900mA, so connecting the SATA power is recommended for bus-powered drives. macOS compatibility may be limited for some features.

Product Disclosure (Amazon)

  • Manufacturer: StarTech.com(スターテック)
  • Seller: オフィス・モア (in 神戸)
  • Fulfilled by: オフィス・モア (in 神戸)
  • ASIN: B00ITJ7X9K
  • Note: This article covers a manufacturer-made product based on Amazon listing details.