QNAP QXG-25G2SF-CX6 Dual-Port 25GbE SFP28 Network Expansion Card
Overview
The QXG-25G2SF-CX6 is a dual-port 25GbE SFP28 network expansion card built on the NVIDIA Mellanox ConnectX-6 Lx SmartNIC controller. It slots into a PCIe Gen4 slot to deliver up to 25 Gbps per port — meaning a QNAP NAS serving video surveillance archives, large-media workflows, or high-throughput backup targets can saturate a 25GbE uplink without the NAS itself becoming the bottleneck. SR-IOV support lets hypervisors and virtualization workloads on compatible QNAP systems carve the physical ports into multiple virtual functions, eliminating the need for additional NICs per VM. RoCE (RDMA over Converged Ethernet) support enables low-latency memory-to-memory transfers between storage nodes — relevant in clustered NAS or high-frequency backup architectures where TCP overhead matters. The low-profile form factor (117.33 mm length, 1-slot width) fits in standard desktop chassis as well as compact rackmount NAS enclosures with low-profile PCIe slots.
Compatibility
Designed for QNAP NAS and rackmount systems that expose a PCIe Gen4 x8 or x16 slot, including high-capacity tower and rack models in the TVS-h, TS-h, and TES series. The card operates at PCIe Gen3 speeds on Gen3 hosts with reduced throughput. SFP28 ports are backward-compatible with SFP+ modules and cables, so existing 10GbE DAC or optical infrastructure can be reused during a phased 25GbE network upgrade — though you will only achieve 10 Gbps on those links until the switch side is also upgraded. Pair with a 25GbE-capable managed switch to realize the full per-port bandwidth. Verify slot availability and chassis PCIe slot depth in your specific QNAP model's hardware compatibility list before ordering, as some compact 1U enclosures may restrict card length or slot count.
Installation Notes
Low-profile bracket is required for 1U and compact rackmount chassis — confirm whether your enclosure ships with or requires a separately sourced low-profile bracket. The card ships at 117.33 mm card length; measure available PCIe slot clearance before installation in depth-constrained enclosures. SR-IOV and RoCE features require driver and firmware versions supported by the host QNAP QTS or QuTS hero firmware; check the QNAP compatibility notes for your NAS OS version before deploying in production. No external power connector is required — the card draws power from the PCIe slot directly.
