StarTech.com PEXUSB321C 1-Port USB 3.2 Gen 2 x 2 PCIe Card - USB-C 20Gbps PCIe 3.0 x 4 Controller - Data Only - Windows/macOS/Linux
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Product Features
Technical Overview
This PCIe add-in card provides a dedicated USB 3.2 Gen 2x2 (20 Gbps) port through a PCI Express 3.0 x4 host interface. The implementation uses the ASMedia ASM3242 controller, which is optimized for high-bandwidth data transfer and low latency.
The card supports USB Attached SCSI Protocol (UASP), which reduces CPU overhead and improves data transfer efficiency compared to the traditional USB Mass Storage Class (BOT) protocol. This is particularly beneficial when working with high-performance NVMe drives, SSDs, or multi-drive enclosures.
Compatibility extends across a wide range of operating systems, with native driver support in Windows 8 and later, modern macOS versions, and Linux kernels 3.5 and above. The card maintains backward compatibility with USB 3.2 Gen 2 (10 Gbps), USB 3.0 (5 Gbps), and USB 2.0 (480 Mbps) devices.
Key Product Advantages
The PEXUSB321C brings next-generation USB performance to systems lacking native USB 3.2 Gen 2x2 support. Its 20 Gbps capability doubles the bandwidth of standard USB 3.2 Gen 2 ports, significantly reducing transfer times for large files and improving responsiveness with high-speed storage.
High-Speed Connectivity
Delivers USB 3.2 Gen 2x2 speeds for rapid data transfers with compatible NVMe drives, SSDs, and high-performance peripherals.
- 20 Gbps maximum throughput
- ASMedia ASM3242 controller
- PCIe 3.0 x4 interface
Broad System Compatibility
Works with Windows, macOS, and Linux systems without requiring additional drivers in most cases. Includes both full-profile and low-profile brackets for flexible installation.
- Windows 8 through 11 support
- macOS 10.13+ compatibility
- Linux kernel 3.5+ ready
Optimized Performance Features
Incorporates UASP support for reduced CPU utilization and faster data transfers with storage devices. Multiple INs capability helps maintain bandwidth efficiency in hub configurations.
- UASP protocol support
- Multiple INs implementation
- Backward compatible with older USB standards
Deployment / Use Cases
This PCIe USB card is designed for desktop systems that require high-speed USB connectivity for data-intensive applications. It serves as an effective upgrade path for older systems or as an expansion solution for systems with limited native USB ports.
Common deployment scenarios include workstation builds where fast external storage is essential, content creation systems that regularly transfer large media files, and server environments that benefit from high-throughput peripheral connections. The card's data-only focus makes it particularly suitable for storage expansion and backup solutions.
Storage Expansion
Connect high-speed external NVMe or SSD enclosures for additional storage capacity with minimal performance compromise.
Workstation Enhancement
Upgrade older systems to support modern USB-C peripherals and storage devices without replacing the entire system.
Physical Profile
The card features a compact plug-in card form factor with dimensions of 3.10" wide × 2" long × 0.90" high (78.74 × 50.80 × 22.86 mm). Its red PCB provides visual distinction in system builds while maintaining professional aesthetics.
Weighing approximately 1.30 ounces (36.85 grams), the card is lightweight yet built with durable components. The included full-profile bracket is pre-installed, with a low-profile bracket provided for smaller chassis configurations. The card meets EU RoHS environmental standards and is manufactured in Taiwan.
- Width
- 3.10" (78.74 mm)
- Height
- 0.90" (22.86 mm)
- Weight
- 1.30 oz (36.85 g)
- Length
- 2" (50.80 mm)
What's in the Box
The package includes everything needed for installation in standard desktop systems.
Highlights
- Adds one USB 3.2 Gen 2x2 (20 Gbps) USB-C port to desktop systems
- Utilizes PCI Express 3.0 x4 interface for maximum bandwidth
- Supports UASP for improved storage device performance
- Compatible with Windows 8 through 11, macOS 10.13+, and Linux 3.5+
- Includes both full-profile and low-profile mounting brackets
- Features ASMedia ASM3242 host controller
- Provides up to 15W (5V @ 3A) power delivery for connected devices
- Backward compatible with USB 3.2 Gen 2, USB 3.0, and USB 2.0 devices
- Data-only port (no video output or Thunderbolt support)
- 2-year limited warranty with RoHS compliance
Specifications
| Specifications | |
|---|---|
| Manufacturer | StarTech.com |
| Manufacturer Part Number | PEXUSB321C |
| Brand Name | StarTech.com |
| Product Name | PCI Express USB Card |
| Packaged Quantity | 1 Each |
| Product Type | USB Adapter |
| Technical Information | |
| Host Interface | PCI Express x4 |
| Media & Performance | |
| UASP Support | Yes |
| Interfaces/Ports | |
| Total Number of USB Ports | 1 |
| Number of USB 3.2 Ports | 1 |
| Software | |
| Operating System Supported | Windows 8,Windows 8.1,Windows 10,Windows 11,Windows Server 2012 R2,Windows Server 2016,Windows Server 2019,Windows Server 2022,Mac OS X 10.13 High Sierra,Mac OS X 10.14 Mojave,Mac OS X 10.15 Catalina,Mac OS X 11.0 Big Sur,Mac OS X 12.0 Monterey,Mac OS X 13.0 Ventura,Linux 3.5 |
| Physical Characteristics | |
| Color Family | Red |
| Product Color | Red |
| Form Factor | Plug-in Card |
| Height | 0.90" (22.86 mm) |
| Width | 3.10" (78.74 mm) |
| Length | 2" (50.80 mm) |
| Weight (Approximate) | 1.30 oz (36.85 g) |
| Miscellaneous | |
| Package Contents | PCI Express USB Card 1x Full Profile Bracket (Installed) 1x Low Profile Bracket 1x Quick-Start Guide |
| Platform Supported | PC,Linux,Mac |
| Country of Origin | Taiwan |
| Environmentally Friendly | Yes |
| Environmental Certification | EU RoHS |
| Environmental Compliance | Restriction of Hazardous Substances (RoHS) 2,Registration, Evaluation, Authorization and Restriction of Chemicals (REACH),Waste Electrical and Electronic Equipment Directive (WEEE) |
| Warranty | |
| Limited Warranty | 2 Year |
User Manual
FAQ
What is the maximum data transfer speed of this USB card?
The StarTech.com PEXUSB321C supports USB 3.2 Gen 2x2 specifications, delivering data transfer speeds up to 20 gigabits per second (Gbps). This represents a significant performance increase over standard USB 3.2 Gen 2 (10 Gbps) and USB 3.0 (5 Gbps) interfaces, making it ideal for high-speed storage devices and data-intensive applications.
Which operating systems are compatible with this PCIe USB card?
This card is compatible with Windows 8, 8.1, 10, and 11, as well as Windows Server 2012 R2 through 2022. It also supports macOS 10.13 High Sierra and later versions, along with Linux distributions using kernel 3.5 or newer. Most modern operating systems include native drivers, eliminating the need for additional software installation.
Can this card be installed in a low-profile desktop chassis?
Yes, the PEXUSB321C includes both a pre-installed full-profile bracket and an additional low-profile bracket for smaller form factor systems. The card itself maintains standard PCIe dimensions while the interchangeable brackets allow installation in various desktop chassis configurations, providing flexibility for different build requirements.
Does this USB-C port support video output or device charging?
No, this is a data-only USB-C port. It does not support DisplayPort Alt Mode for video output, USB Power Delivery for charging devices, or Thunderbolt connectivity. The port is specifically designed for high-speed data transfer applications, with power delivery limited to standard USB bus power (up to 15W at 5V/3A) for connected devices.
What is UASP support and how does it benefit performance?
UASP (USB Attached SCSI Protocol) is an advanced data transfer protocol that reduces CPU utilization and improves efficiency compared to the traditional USB Mass Storage Class (BOT) protocol. When used with compatible storage devices, UASP can significantly increase transfer speeds and reduce latency, particularly beneficial for SSD and NVMe drive performance.
Is this card backward compatible with older USB standards?
Yes, the PEXUSB321C maintains full backward compatibility with USB 3.2 Gen 2 (10 Gbps), USB 3.0 (5 Gbps), and USB 2.0 (480 Mbps) devices. The card will automatically negotiate the appropriate speed with connected peripherals, ensuring compatibility with a wide range of existing USB devices while providing maximum performance with newer USB 3.2 Gen 2x2 compatible equipment.
| Qty | Price | Available |
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