StarTech.com PEX4SFF8639 · Drive adapter

MPN / P/N

PEX4SFF8639

Manufacturer designation

U.2 to PCIe Adapter for 2.5" U.2 NVMe SSD - SFF-8639 - x4 PCI Express 4.0 - TAA

Manufacturer conditions

Some U.2 drives make use of a feature called PWDIS which; allows for remote power cycling of drives. Only Rev 03 and up of; the PEX4SFFD8639 support this feature and work with drives; that use it.

Colour

Red

Material

Steel

Product length

6.5 in [16.5 cm]

Product width

4.8 in [12.2 cm]

Product height

0.9 in [22 mm]

Product weight

2.3 oz [65 g]

Operating temperature

5C to 50C (41F to 122F)

Storage temperature

-25C to 70C (-13F to 158F)

Humidity

15% ~ 90% RH

RAID

No

Hot-swap capability — manufacturer conditions

No

Fans Included? Yes/No

No

Interface

PCI Express

Bus type

PCI Express

Number of drives

1

Drive size

2.5in

Compatible drive types

U.2 (PCIe, NVMe, SFF-8639)

Drive installation

Fixed

Supported drive dimensions — source designation

15mm; 12.5mm; 9.5mm; 7mm; 5mm

LED Indicators

1 - Activity Terminal/Header

Host Connector 1 (Quantity)

1

Host Connector 1

PCI Express x4

Connector 1 (Quantity)

1

Connector 1

U.2 (PCIe, AHCI / NVMe)

Documented selection limits

Match the exact host interface, peripheral/device protocol, connector, firmware, OS/driver and power requirements before ordering. Published maximum rates are interface limits, not guaranteed application throughput. No universal device or current/future OS compatibility is implied. Match SATA versus PCIe/NVMe, M.2 key/length, PCIe generation/lane width and required bifurcation. A passive adapter cannot add a missing host protocol. Multi-drive/RAID and bootability require the explicitly stated host/firmware support; storage drives are not automatically included.

Specification source: StarTech.com ↗
Checked against documentation: 16.10.2026