2.5G Dual RJ45 Port PCI-E Network Card with RTL8125B Conrtoller, QFly 2.5Gb Ethernet Adapter Card Compatible with 100/1000Mbps/2.5G, Support Windows/Linux

I picked up two of these QFly 2.5G dual-port PCIe cards and they’ve been phenomenal for the price. Easy install, solid performance on both Windows and Linux. The only hiccup was with PCI passthrough — the Realtek RTL8125B chipset doesn’t play nice with virtual machine passthrough. I had to fall back to a VirtIO setup for my router VM. Not ideal, but it works — and that’s on the chipset, not the card. Pros: Reliable 2.5G speeds Plug-and-play on most systems Great price Dual ports on a PCIe x1 slot — perfect for compact or low-slot systems Cons: Realtek chip has known passthrough issues in VM setups Verdict: 5 stars. Great card, just avoid it for passthrough-heavy virtualization.

Installed this into a new system running Debian 12 (bookworm) and it came up plug-n-play with no issues or fiddling, no doubt thanks to the new non-free-firmware setup. Transferred 20 TB over it with no problem, though it sat at ~80C the whole time - this could be due to not having sufficient airflow at that point, can't say for sure. In any case, I'd recommend you watch the temps on this one. Also note it was actually only running at 1GBit speeds for that, as the machine on the other end wasn't configured properly. But the network segment on the QFly end was 10Gbit. Then I moved the card to a Windows 10 machine and the drivers didn't come up automatically or via a Windows Update search using a different connected NIC. I had thrown out the packaging and CD at that point and couldn't find drivers online. The flash drive with the drivers comes up normally on Windows (*), and you just point Device Manager's driver search at that. Haven't put it through its paces on Windows yet, but it is working. (*) Note that if you want to mount the pack-in flash drive on linux you may have issues, since (on the one I got) there is no partition table(!) - fdisk gets confused by it and claims a nonsense partition layout because it's actually a bare filesystem, so you want to "mount /dev/sdX", NOT "mount /dev/sdX1". Don't know if automount systems can handle this gracefully or not. (Also final words: the review that says that this NIC doesn't work with "linux (pfsense)" is incorrect - the card works fine on linux, but pfsense isn't linux, it's FreeBSD. Always double-check compatibility for newer hardware before you buy if you're working with BSD, compatibility is generally worse than with linux.) No ragrets.

This is an initial review of the QFly 10 Gbps PCIe card on Debian 12 running kernel 12.12. No long term data available yet. The card was immediately recognized by Debian. No drivers needed to be loaded. Just needed to set IP, gateway and DNS addresses. I conducted sustained iperf3 tests through a 10G switch to a PC with the same Marvell controller chip on the motherboard. Initial sustained speeds were 9.42 Gbps (MTU=1500) until I set jumbo frames to MTU=9000 on both of the Marvell controllers. Once jumbo frames were set, sustained throughput jumped to 9.91 Gbps. The Marvell AQC113C controller chip supposedly supports 16K jumbo frames. The switch supports 12K jumbo frames which makes the switch the bottleneck for my test's max jumbo frame size. 9K jumbo frames is a 6:1 reduction (from MTU=1500) in packet headers to process. 12K would be an 8:1 reduction in packet header processing possibly squeezing out a little more throughput. Throughput was consistent with 1, 2, 10 and 20 thread iperf3 tests. The card is tiny and the heat sink appears to be doing its job. The heat sink appeared larger than the heat sinks of its competitors, thus a purchase consideration. After a sustained hour run @ 9.91 Gbps, the passive heat sink was barely warm in the center with no case fans blowing on it. CPU utilization on an i7-6700 was [4-6]% under full bandwidth iperf3 tests (depending on selected tuned profile). Initial tests were done with new short and long Cat 8 cables. A second round of tests were conducted with 10+ year old house wiring with cable lengths up to 75 feet. Throughput was the same with the old cables as it was with the new Cat 8 cables. So far so go. Now to see if it lasts. Hope this information is helpful to someone. Update: Tried 12K jumbo frames which maxed out at 9.93 Gbps sustained throughput with ZERO retries, up from 9.91 Gbps with 9K jumbo frames. See attached green highlight for 1 hour sustained max throughput test. 4.06 TBytes transferred in 1 hour.

Bought three of these, and using them on a 2.5 Gbps switch for the moment. This is the newer AQC113C, so it's PCIe 4.0, so you don't need to have full 4X lanes to get full 10Gbps speeds. Even 4.0 1X should manage full 10Gbps link speed, and 3.0 1X in theory should work, but it's nice to have all 4.0 4X wired up on the card side, in case you want every last bit of performance. I have this running on Windows 11, I used the drivers from the included USB drive to get online, then grabbed the newest driver from Windows Update. No issues yet. I have this running on Arch Linux. It was detected and set up automatically, using in-kernel drivers. The Marvell ACQtion driver is included in the main Arch kernel, other distros have varying support. Check twice before buying, and you'll be happy! Performance tests with a 10Gbps switch to be added later.

Much better than other AQC113 products. I purchased a different brand 10GBe NIC (Vimin) which worked fine but was disappointed with slot not aligning properly. I was afraid this QFly product was going to be the same as it looked similar. However, this QFly product is way better in terms of manufacturing quality. The PCB construction, heatsink and slot alignment are so much better. It also includes a screwdriver, mini CD and compact 1GB USB with driver which the vimin product did not have. I am getting full 10gbps link speed as well. Highly recommend

Good 10GbE card! Impressed with the complete packaging including CD and USB stick for drivers. Working well in my system with both Windows 11 and Server 2019 systems. More details in my blog post - do search for "Archimago QFly" in google for the article in Archimago's Musings in Feb 2024.

worked great for a few months and started crashing none-stop when i began gaming again, tried everything from re-installing network card in windows, re-installing windows entirely, combination of all kinds or different settings and nothing worked. found a few cases like me after a google search. switched back to network card on motherboard and no problem.