1.25G Gigabit Ethernet Converged Network Adapter (NIC) with Intel I350AM2 Controller - Compatible for Intel I350-T2, Dual Copper RJ45 Ports, PCI-E 2.1 X4

Went for the Intel 82576 dual gigabit cards to install into three pfsense boxes. For anyone else thinking of using for PFSense, it was a doddle, intel drivers automatically recognised. They perform at 1Gbps up/down on a 1Gb WAN connection on PFSense, and exactly 1gbps on the LAN side, so no complaints there! No issues with any of the three in around 6 months of deployment at three different sites. I can also confirm compatibility with VLAN tagging in PFSense.*Edit Feb 2020, in total I have 5 of these cards cards running 24/7 for over two years now without issues.

This card is detected by Windows 10 and doesn't require additional drivers to use it as a basic network adapter which might suit some people however, as a dual port NIC, you are mostly likely wanting to do something more advanced.If you want to use VLANs, Teaming and other advanced networking features then this card is not supported by the latest Intel NIC drivers. The Intel Network Configuration Utility software detects the card as installed but says it's not supported. For Windows users this means you will need to use a Server OS or older version of Windows to leverage the advanced functionality of this card.

The description of this device states "PCI Express* 2.0. 2.5 GT/s x1 Lane", however PCI Express 2.0 should be 5.0 GT/s per lane so there's a contradiction there.Unfortunately, this device can not sustain maximum throughput on both ports at the same time. I ran some iperf3 tests and a single port sustained 986Mbps throughput, but once I ran two concurrent iperfs using both ports, the throughput on each port was only 490Mbps.This card is useful for getting two extra network ports when you've only got a PCIe x1 slot available, but don't expect full speeds through both at the same time.Update: looking into the speed of this adapter again, it appears that the chip it is based on, the Intel 82576, uses the PCI Express v2.0 interface but is limited to 2.5 GT/s per lane instead of the 5.0 GT/s that PCIe v2.0 should be capable of. The chip supports x1, x2 and x4 lanes and probably relies on having x4 to get full throughput on both ports simultaneously, but this card only provides it with x1 lanes to connect to the host.

Working under Ubuntu LTS 20.04 using the IGB Driver.The MAC refers to Beijing Sinead Technology Co., Ltd. in China not Intel Corp so maybe it's a clone of the 82576 chip and not genuine Intel hardware.LAG and VLAN working fine.As people have mentioned, trying to use full 4Gbps bandwidth causes a drop in speed, even though it's connected to a 4x@PCIe2 Slot as confirmed by the LSPCI report which gives 16GBps in each direction, it should have more than enough bandwidth to saturate.LSPCI Report: LnkCap: Port #0, Speed 2.5GT/s, Width x4, ASPM L0s L1, Exit Latency L0s <4us, L1 <64us ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp- LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk+ ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt- LnkSta: Speed 2.5GT/s (ok), Width x1 (downgraded) TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-Here's what LSHW reports for both interfaces:description: Ethernet interface product: 82576 Gigabit Network Connection vendor: Intel Corporation physical id: 0 bus info: pci@0000:02:00.0 logical name: enp2s0f0 version: 01 serial: 80:61:5f:xx:xx:xx size: 1Gbit/s capacity: 1Gbit/s width: 32 bits clock: 33MHz capabilities: pm msi msix pciexpress bus_master cap_list rom ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=igb driverversion=5.6.0-k duplex=full firmware=1.2.1 ip=xxx.xxx.xxx.xxx latency=0 link=yes multicast=yes port=twisted pair speed=1Gbit/s

It's also based on the highly supported and reliable Intel I210 network circuit, which is exactly why I bought this add in card. I am using it as the WAN-in adapter on my Pfsense Router, which is expected to be up and serving 24/7, I have had it for a few months so far and no issues at all.Pfsense uses FreeBSD OS, and compatibility with this adapter is great. Highly recommended.

Fitted to my test/lab pc for pfsense experiments and works a treatIt has the intel chipset that pfsense needs to run correctly

Great for my unRAID build while I'm waiting for an update to enable my on-board ethernet port. Easy to install, worked without any setup. Perfect.

Rock solid, running OPNsense 24/7 with zero issues