Network interface adapter InLine 51125T — PCIe network card, model 51125T

The InLine 51125T PCIe network card adds a 2.5 Gigabit Ethernet RJ45 port to desktop PCs, workstations and industrial computers. It uses the Realtek RTL8125B chipset and connects through a PCIe x1 interface (compatible with x1, x4, x8 and x16 slots). The card supports multiple link speeds and advanced networking functions useful for servers, NAS, virtualization and multimedia streaming. The package includes a low-profile bracket, driver CD and a multilingual user manual.

Advantages

The card delivers up to 2.5 Gb/s over standard Cat 5e cabling, avoiding rewiring for many installations. Its Realtek RTL8125B chipset implements features such as VLAN and double-VLAN, jumbo frames up to 16 KB, RSS, hardware CRC/ECC, Wake-on-LAN and virtualization offloads (VMQ, VMDq). Broad OS support for Windows and common Linux distributions ensures easy integration into existing environments.

Suitable for

• Adding a fast wired port to desktop PCs and workstations
• Connecting NAS and home or small office servers
• Multimedia streaming and large file transfers
• Virtualization hosts and VMs requiring network offload features

Key specifications

• Interface: PCIe v2.1 x1 (compatible with x1, x4, x8, x16)
• Network connector: 1 × RJ45
• Chipset: Realtek RTL8125B
• Supported speeds: 2.5 Gb/s, 1 Gb/s, 100 Mb/s, 10 Mb/s
• Supported protocols and features: Auto-negotiation, Auto-MDI/MDI-X, IEEE 802.3x flow control, VLAN (IEEE 802.1Q/802.1ad), priority (IEEE 802.1p), Energy Efficient Ethernet (IEEE 802.3az), jumbo frames up to 16 KB, RSS, hardware CRC/ECC, Wake-on-LAN, RealWoW!, VMQ, VMDq, PTP time services (IEEE 1588v1/v2, IEEE 802.1AS)
• Cable requirements: Cat 5e or higher for 2.5 Gb/s (up to 100 m)
• Operating temperature: 0 °C to 70 °C
• Storage temperature: -40 °C to 70 °C
• Maximum humidity: 90% non-condensing
• Supported operating systems: Windows 7/8/8.1/10/11, Windows Server (2008–2019), Linux

How to use

Install the card into an available PCIe x1, x4, x8 or x16 slot, secure the bracket and connect a Cat 5e (or better) Ethernet cable to the RJ45 port. Boot the system and install the provided drivers or obtain up-to-date drivers from the manufacturer if required. Configure link speed, VLANs or other advanced features through the operating system network settings or the NIC driver utility according to your network design.

Usage recommendations

For 2.5 Gb/s operation use Cat 5e or higher cabling and keep runs within 100 m. Use the low-profile bracket for small form factor cases. Enable driver-offload features (VMQ, VMDq, RSS) on virtualization hosts to reduce CPU load and improve network throughput.