Products / Host Cards / PCIe x8 / External PCIe (SFF-8644)


External PCIe (SFF-8644 1x2) to PCIe x8 Gen 3 Switch Host Card

EP8X-PCIE8XG302|External PCIe (SFF-8644 1x2) to PCIe x8 Gen 3 Switch Host Card
  • Designed with 16-Lane, 3-Port PCIe Gen 3 (8.0 GT/s) Switch
  • Supports the following Mode configurations:
    • Mode2 = x8 x8
    • Mode3 = x8 x4x4
    • Mode3+ = x4x4 x8
  • Spread Spectrum Clock (SSC) Isolation Support
    • Optional REFCLK inputs can be selectively enabled to Support Isolation of Multiple SSC Domains
  • External PCIe Fixed-Side Connectors: SFF-8644
  • Supports the following Copper and AOC Cable
    • CB-S0020: PCIe Gen 3 External Mini-SAS HD (SFF-8644) 4x plug Cable
    • P3MSHDAOC: PCIe Gen 3 External Mini SAS HD (SFF-8644) 4x plug AOC
  • Supports Low Profile PCI Form Factor

EP8X-PCIE8XG302 is External PCIe x8 Gen 3 Switch Host Card. Designed to overcome the limited PCIe connectivity of most desktop computers, the EP8X-PCIE8XG302 can be quickly and easily set up for external expansion. No additional software or drivers are needed.

The SSC Isolation feature allows the PCIe Packet Switch to be used in a Spread Spectrum Clocking (SSC) environment and communicate with devices that are operating in a Constant Frequency Clocking (CFC) environment.
This capability is necessary for system in which the upstream Port connects to the SSC source, while downstream Ports connect to Links running on CFC domains.

In particularly rugged environments, your desktop computer can be placed at a secure location up to 100 meters away (using PCIe A.O.C). High-performance and reliable communication are maintained with the well-shielded extension cable or A.O.C (Active Optical Cable).

Utilizing the standard PCI Express Switch, the 16-Lane/5-Port PCI Express Gen 3 (8 Gbps) Switch provides the most efficient fan-out solution.

EP8X-PCIE8XG302 supports the following multiple Port configuration options:

Technical Specifications
PCIe interface 16-Lane, 3-Port PCIe Gen 3 (8.0 GT/s) Switch
  • EP8X-PCIE8XG302-H
    • Upstream Port: PCIe x8 Edge Connector
    • Downstream Port: SFF-8644 Connectors
  • EP8X-PCIE8XG302-T
    • Upstream Port: SFF-8644 Connectors
    • Downstream Port: PCIe x8 Edge Connector
Key Features
  • Standards Compliant
    • PCI Express Base Specification, r3.0 (compatible w/ PCIe r1.0a/1.1 & 2.0)
    • PCI Power Management Spec r1.2
    • Microsoft Windows Logo Compliant
    • Supports Access Control Services
    • Dynamic link-width control
    • Dynamic SerDes Speed Control
  • High Performance
    • performancePAK
      • Multicast
      • Dynamic Buffer/FC Credit Pool
    • Non-blocking switch fabric
    • Full line rate on all ports
    • Cut-Thru packet latency of less than 100ns between symmetric (x4 to x4) ingress and egress Ports
    • 2KB Max Payload Size
  • Quality of Service (QoS)
    • Traffic Class Queuing
    • Eight Traffic Classes per port
    • Weighted round-robin source port arbitration

PCIe Port Status LEDs

  • Slow Blink: Gen 1
  • Fast Blink: Gen 2
  • Solid: Gen 3


  • LEDP0: Port0 LED
  • LEDP1: Port1 LED
  • LEDP2: Port2 LED


SW1-1&2: Max PCIe Data Rate Setting
SW 1-1 SW 1-2 PCIe Data Rate
ON* OFF* Gen 3 (8.0 GT/s)
OFF OFF Gen 2 (5.0 GT/s)
OFF ON Gen 1 (2.5 GT/s)
SW1-3&4: CFC(100MHz) Spread Setting
SW 1-3 SW 1-4 CFC(100MHz) Spread
OFF ON Down -0.5
OFF* OFF* No Spread
ON OFF Down -0.75
SW2-1&2: PCIe Mode Setting
SW 2-1 SW 2-2 Mode
OFF ON x8, x8
ON OFF x8, x4 x4
SW2-1&2: PCIe Mode Setting
SW 2-3 Host Target

x8, x8

Port1 OFF Port0 ON

x8, x4 x4

Port0 ON Port0 OFF
SW2-4: NT Port Setting
SW 2-4 NT Port
ON Port2
OFF* Disable
Jumper for EP8X-PCIE8XG302-H
  • JP1: SSC RefCLK Enable
    • C-1: Port1 (x8, x8 mode)
    • C-0: Port0 (x8, x4 x4 mode)
Computer Platform Requirements Desktop computer equipped with a PCIe x8, x16 slot
Physical Dimensions
  • 84(H)x134(L) mm
  • NW: 78g
Available Models

For Host: EP8X-PCIE8XG302-H

For Target: EP8X-PCIE8XG302-T

SFF-8644 1x2 Fixed-Side Connector Pinout
Optional Accessories
  • Low Profile PCI Bracket (S-BR-00248-12-1020)
  • SFF-8644 Cable (CB-S0020)
  • SFF-8644 AOC (P3MSHDAOC)
  • Expansion Docking Board (PCIEX16D02)