StarTech.com PEX4SFF8639 U. 2 to PCIe Adapter for 2.5" U. 2 NVMe SSD - SFF-8639 PCIe 3.0 x 4 - Red Steel
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Product Features
Technical Overview
This adapter utilizes a PCI Express 3.0 x4 host interface that delivers up to 32 Gb/s of bandwidth, fully supporting the performance capabilities of modern U.2 NVMe SSDs. The design maintains backward compatibility with PCIe 2.0 and PCIe 1.0 motherboards, ensuring broad system compatibility across different generations of hardware.
The adapter's SFF-8639 connector is specifically engineered for 2.5" U.2 form factor drives, providing secure physical and electrical connections. Four drive-mounting screws included with the adapter ensure stable SSD installation, preventing movement or disconnection during system operation or transportation.
Relevant factors for this section include Color Family, Product Color, Product Material, Package Contents. 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 U.2 to PCIe adapter delivers several practical advantages for storage expansion projects. The direct-mount design eliminates cable management challenges while ensuring reliable connections between SSD and adapter. This approach reduces points of failure and simplifies system assembly compared to cable-based solutions.
Performance Optimization
By providing a dedicated PCIe 3.0 x4 connection, the adapter maintains the full performance potential of U.2 NVMe SSDs, avoiding bottlenecks that can occur with alternative connection methods.
- 32 Gb/s bandwidth
- Full NVMe protocol support
- No performance degradation
Simplified Integration
The adapter's design focuses on ease of use with features that streamline system integration and maintenance.
- OS-independent operation
- No additional power cables
- Quick-start guide included
Deployment / Use Cases
This adapter is ideal for workstations, servers, and custom PC builds where U.2 NVMe storage expansion is required but motherboard U.2 connectors are unavailable. It enables system builders to incorporate high-speed U.2 SSDs into standard PCIe slots, expanding storage options without motherboard limitations.
Common deployment scenarios include adding U.2 NVMe storage to existing systems for video editing workstations, database servers, or high-performance computing applications. The adapter also serves as a cost-effective solution for testing U.2 SSDs in various systems without requiring native U.2 motherboard support.
Relevant factors for this section include Color Family, Product Color, Product Material, Package Contents. 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.
Physical Profile
The adapter measures 6.50" in length, 4.80" in width, and 0.90" in height (165.10 x 121.92 x 22.86 mm), with a compact form factor that fits standard PCIe slots without interfering with adjacent components. The steel construction provides structural integrity while the red finish offers visual identification in multi-adapter installations. The low-profile design and lightweight construction (2.30 oz) minimize impact on system airflow and weight distribution.
- Width
- 4.80" (121.92 mm)
- Height
- 0.90" (22.86 mm)
- Weight
- 2.30 oz (65.20 g)
- Length
- 6.50" (165.10 mm)
What's in the Box
The package includes everything needed for immediate installation and use of the adapter with your U.2 NVMe SSD.
Highlights
- Converts 2.5" U.2 NVMe SSDs to PCIe 3.0 x4 slots
- Direct-mount design eliminates adapter cables
- Backward compatible with PCIe 2.0 and PCIe 1.0 motherboards
- OS-independent operation with no drivers required
- Steel construction with red finish for durability
- Includes drive-mounting screws for secure SSD installation
- CE, FCC, and EU RoHS certified
- TAA compliant for government procurement
- 2-year limited warranty
- Compact dimensions: 6.50" x 4.80" x 0.90"
Specifications
| Specifications | |
|---|---|
| Manufacturer | StarTech.com |
| Manufacturer Part Number | PEX4SFF8639 |
| Brand Name | StarTech.com |
| Product Name | U.2 to PCIe Adapter for 2.5" U.2 NVMe SSD - SFF-8639 - x4 PCI Express 3.0 |
| Packaged Quantity | 1 Each |
| Product Type | U.2 to PCI Express Adapter |
| Physical Characteristics | |
| Color Family | Red |
| Product Color | Red |
| Product Material | Steel |
| Height | 0.90" (22.86 mm) |
| Width | 4.80" (121.92 mm) |
| Length | 6.50" (165.10 mm) |
| Weight (Approximate) | 2.30 oz (65.20 g) |
| Miscellaneous | |
| Package Contents | U.2 to PCIe Adapter for 2.5" U.2 NVMe SSD - SFF-8639 - x4 PCI Express 3.0 4 x Drive-mounting Screws 1 x Quick-start Guide |
| Certifications & Standards | CE FCC |
| 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) |
| Country of Origin | Taiwan |
| TAA Compliant | Yes |
| Warranty | |
| Limited Warranty | 2 Year |
User Manual
FAQ
Does this adapter require additional power connections?
No, this adapter draws all necessary power directly from the PCIe slot. The PCIe 3.0 x4 interface provides sufficient power for both the adapter circuitry and the connected U.2 SSD. This eliminates the need for separate power cables, simplifying installation and reducing cable clutter within your system. The design ensures stable power delivery for consistent SSD performance.
Can I use this adapter with PCIe 4.0 or PCIe 5.0 motherboards?
While the adapter itself is designed for PCIe 3.0 x4 operation, it will function in PCIe 4.0 and PCIe 5.0 slots through backward compatibility. The adapter will operate at PCIe 3.0 speeds when installed in newer generation slots. For optimal performance with PCIe 4.0 or 5.0 systems, ensure your U.2 SSD and system configuration support the desired performance levels, as the adapter maintains the PCIe 3.0 interface specification.
What certifications does this adapter carry for environmental compliance?
This adapter is certified for CE and FCC compliance and meets EU RoHS (Restriction of Hazardous Substances) standards. It also complies with REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) and WEEE (Waste Electrical and Electronic Equipment Directive) requirements. These certifications ensure the product meets European environmental regulations for hazardous substance restrictions and responsible end-of-life disposal practices.
What connectivity or interface options are available?
Connectivity details help confirm how StarTech.com U.2 to PCIe Adapter for 2.5" U.2 NVMe SSD - SFF-8639 PCIe Adapter - x4 PCI Express 4.0 - NVMe PCIe Adapter - U.2 PCIe - a (PEX4SFF8639) can integrate with your network, accessories, and surrounding peripherals before rollout or replacement planning.
What form factor or physical profile is listed?
The listed physical configuration is 0.90" (22.86 mm), which helps buyers judge placement, comfort, or installation fit in the intended environment.
What compatibility details are mentioned?
StarTech.com U.2 to PCIe Adapter for 2.5" U.2 NVMe SSD - SFF-8639 PCIe Adapter - x4 PCI Express 4.0 - NVMe PCIe Adapter - U.2 PCIe - a (PEX4SFF8639) is described for practical deployment use, and the specification set helps buyers confirm fit, compatibility, and expected day-to-day operation.
| Qty | Price | Available |
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