StarTech.com PEXUSB3S42 4-Port PCIe USB 3.0 Card - 3 External + 1 Internal - 5Gbps - UASP Support - Low-Profile Bracket Included
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Product Features
Technical Overview
This USB 3.0 adapter leverages PCI Express x1 host connectivity to deliver sustained 5 Gbps throughput across all four ports. The implementation includes UASP (USB Attached SCSI Protocol) support, which reduces CPU overhead and improves data transfer efficiency compared to traditional BOT (Bulk-Only Transfer) protocols.
The card features an optional SATA power connector that provides up to 900mA per USB port, ensuring stable power delivery for bus-powered peripherals. All four ports comply with USB 3.2 Gen 1 specifications while maintaining electrical and mechanical compatibility with earlier USB standards.
Relevant factors for this section include Host Interface, UASP Support. When those points are considered together, they give buyers a clearer picture of how the product is equipped, how it fits into deployment, and what kind of day-to-day role it is meant to support.
Key Product Advantages
This expansion card addresses common connectivity limitations in business and workstation environments where USB port availability constrains peripheral deployment. The combination of external and internal port placement provides flexible connection options for both front-panel and internal device requirements.
Universal Compatibility
Supports Windows XP through Windows 11, Windows Server editions from 2008 R2 to 2019, and Linux distributions with kernel 2.6.31 or later. The PCIe x1 interface works with any available PCI Express slot regardless of length.
- Native OS driver support
- No additional software required for modern Windows versions
- Linux kernel compatibility from 2.6.31+
Dual Form Factor Ready
Includes both standard and low-profile brackets, enabling installation in full-size towers and compact small form-factor systems without separate purchase of mounting hardware.
- Low-profile bracket included
- Tool-free bracket swapping
- Fits standard and SFF cases
Deployment / Use Cases
The PEXUSB3S42 serves as a practical solution for expanding USB connectivity in systems where motherboard ports are fully utilized or insufficient for current peripheral demands. Its 5 Gbps throughput makes it suitable for external storage devices, high-speed data transfer applications, and multi-peripheral workstation configurations.
Common deployment scenarios include adding front-panel USB 3.0 ports to cases lacking native support, connecting multiple external storage drives for backup or media workflows, and expanding connectivity for peripheral-intensive applications like point-of-sale systems, digital signage controllers, or laboratory equipment interfaces. The internal port proves valuable for connecting chassis-mounted card readers, internal USB devices, or secure authentication dongles.
Workstation Expansion
Adds high-speed ports for external SSDs, docking stations, and multiple peripherals in creative, engineering, or financial workstation environments.
Legacy System Modernization
Brings USB 3.0 speeds to older systems with only USB 2.0 ports, extending hardware usefulness while maintaining backward compatibility.
Physical Profile
The black plug-in card measures 4.70 inches in height, 3.40 inches in length, and 0.70 inches in width, with a weight of approximately 1.90 ounces. This compact form factor ensures compatibility with most desktop chassis while the low-profile bracket option accommodates space-constrained small form-factor systems. The card's standard PCI bracket design facilitates secure mounting in any available expansion slot.
The physical profile is practical for deployment planning because the dimensions and weight are clearly defined: 4.70" (119.38 mm), 0.70" (17.78 mm), 1.90 oz (53.86 g). This helps confirm rack, shelf, desk, or cabinet fit before installation.
- Width
- 0.70" (17.78 mm)
- Height
- 4.70" (119.38 mm)
- Weight
- 1.90 oz (53.86 g)
- Length
- 3.40" (86.36 mm)
What's in the Box
The package includes all necessary components for immediate installation and operation.
Highlights
- Adds four USB 3.0 ports (3 external, 1 internal) at 5 Gbps speeds
- PCI Express x1 interface with PCIe 2.0 compliance
- UASP support reduces CPU overhead for faster data transfers
- Backward compatible with USB 2.0 and 1.x devices
- Includes low-profile bracket for small form-factor systems
- Optional SATA power connector provides up to 900mA per port
- Native driver support in Windows 8.1, 8, 7, and Linux kernel 2.6.31+
- Supports Windows XP through Windows 11 and Windows Server editions
- Compact dimensions: 4.70" H × 3.40" L × 0.70" W
- 2-year limited warranty with environmentally friendly construction
Specifications
| Specifications | |
|---|---|
| Manufacturer | StarTech.com |
| Manufacturer Part Number | PEXUSB3S42 |
| Brand Name | StarTech.com |
| Product Name | 4-Port PCI Express USB 3.0 Card - 5Gbps |
| Packaged Quantity | 1 Each |
| Product Type | USB Adapter |
| Technical Information | |
| Host Interface | PCI Express x1 |
| Media & Performance | |
| UASP Support | Yes |
| Interfaces/Ports | |
| Total Number of USB Ports | 4 |
| Number of USB 3.2 Ports | 4 |
| Number of SATA Ports | 1 |
| Software | |
| Operating System Supported | Windows XP,Windows Vista,Windows 7,Windows 8,Windows 8.1,Windows Server 2008 R2,Windows Server 2012,Windows Server 2016,Windows Server 2019,Linux,Windows 10,Windows 11 |
| Physical Characteristics | |
| Color Family | Black |
| Product Color | Black |
| Form Factor | Plug-in Card |
| Height | 4.70" (119.38 mm) |
| Width | 0.70" (17.78 mm) |
| Length | 3.40" (86.36 mm) |
| Weight (Approximate) | 1.90 oz (53.86 g) |
| Miscellaneous | |
| Package Contents | 4-Port PCI Express USB 3.0 Card - 5Gbps 1 x Low-Profile Bracket 1 x Driver CD 1 x Instruction Manual |
| Platform Supported | PC,Linux |
| Country of Origin | China |
| Environmentally Friendly | Yes |
| Warranty | |
| Limited Warranty | 2 Year |
User Manual
FAQ
What types of computers is this USB 3.0 card compatible with?
The StarTech.com PEXUSB3S42 works with desktop computers featuring an available PCI Express x1, x4, x8, or x16 slot. It includes both standard and low-profile brackets, making it compatible with full-size tower cases and compact small form-factor systems. The card requires a motherboard with PCIe connectivity and supports both modern and legacy Windows operating systems alongside Linux distributions.
How many USB ports does this card provide and what are their configurations?
This expansion card delivers four total USB 3.0 ports operating at 5 Gbps. The configuration includes three external ports for connecting peripherals like external drives, printers, or cameras, plus one internal port designed for chassis-mounted devices such as card readers or security dongles. All ports support USB 3.2 Gen 1 specifications while maintaining backward compatibility with USB 2.0 and 1.x devices.
What operating systems does this USB 3.0 card support?
The card supports Windows XP, Vista, 7, 8, 8.1, 10, and 11, along with Windows Server 2008 R2, 2012, 2016, and 2019 editions. Linux compatibility begins with kernel version 2.6.31 or later. Modern Windows versions include native driver support, while older systems may utilize the included driver CD. This broad OS compatibility ensures deployment flexibility across diverse computing environments.
Does this card support UASP and what benefits does it provide?
Yes, the PEXUSB3S42 includes UASP (USB Attached SCSI Protocol) support. UASP reduces CPU overhead during data transfers by enabling command queuing and parallel processing, which can improve transfer speeds by up to 30% compared to traditional BOT (Bulk-Only Transfer) protocols. This enhancement proves particularly beneficial when transferring large files to external SSDs or high-performance storage devices.
What power options are available for connected USB devices?
The card includes an optional SATA power connector that provides up to 900mA per USB port when connected to a power supply. This ensures stable operation for bus-powered devices like external hard drives that require more current than the PCIe slot alone can deliver. Without the SATA power connection, ports deliver standard bus power compliant with USB specifications for lower-power peripherals.
What warranty coverage comes with this USB 3.0 expansion card?
StarTech.com provides a 2-year limited warranty for the PEXUSB3S42, covering defects in materials and workmanship under normal use. The product features environmentally friendly construction and originates from manufacturing facilities in China. Documentation and driver support remain available through StarTech.com's technical resources alongside the included instruction manual and driver CD.
| Qty | Price | Available |
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