QNAP QXP-820S-B3408 Dual-Port SAS 12Gb/s PCIe Host Bus Adapter

Overview

The QXP-820S-B3408 is a dual-port external SAS 12Gb/s PCIe host bus adapter designed to expand raw storage capacity on QNAP NAS systems by linking them directly to TL-series SAS JBOD enclosures and REXP expansion units. If your NAS has filled its internal bays and you need additional shelf capacity without replacing the unit, this card slots into an available PCIe lane and hands the NAS a wide-port connection to external enclosures — no external controller required. The tri-mode controller supports 12Gb/s SAS, 6Gb/s SATA, and PCIe (NVMe) up to 8.0 GT/s, which means the same card can handle mixed enclosure types as your storage footprint grows. Each Mini-SAS HD port carries a wide port aggregating four SAS signals, so a single cable run to an enclosure delivers the full bandwidth of all four lanes simultaneously — relevant when streaming high-bitrate surveillance footage from many cameras into a high-drive-count JBOD shelf.

Compatibility

The QXP-820S-B3408 is designed for use with QNAP NAS systems that provide an available PCIe slot. It connects to QNAP TL-series SAS JBOD storage expansion enclosures (e.g. TL-D400S, TL-R1200S-RP, TL-R400S) and REXP expansion units via Mini-SAS HD (SFF-8644) cabling. The tri-mode Broadcom controller also supports SATA-attached and NVMe-attached devices within compatible enclosures, making it forward-compatible with mixed-media shelves. Verify PCIe slot availability and lane count on your specific NAS model before ordering — a x8 physical slot is typical but lane negotiation varies by chassis. For surveillance deployments, pairing this card with a QNAP NVR or NAS acting as a video recorder and a high-capacity TL-series JBOD is the standard path to multi-petabyte local retention without an external storage controller. If you are also planning network infrastructure, review your PoE switch capacity alongside storage planning to ensure end-to-end throughput is balanced.

Installation Notes

Install the card into a compatible PCIe slot in your QNAP NAS with the system powered down. Use Mini-SAS HD (SFF-8644) external cables — not included — to connect each port to a TL or REXP enclosure. The wide-port architecture means a single SFF-8644 cable carries four SAS lanes; do not substitute with narrow-port SAS cables. NVMe passthrough via PCIe requires enclosure-side NVMe support; standard SAS JBOD enclosures operate in SAS/SATA mode only. Confirm QNAP firmware compatibility for your NAS model on the QNAP compatibility list before deployment.