Syba 1 Port 10 Gigabit Ethernet Network Card - PCIe x4 10Gb 10GBASE-T NIC AQTION AQC107-10Gbps Ethernet PCI-Express x4 Adapter, SD-PEX24055

Low price, works, and is Multi-Gig so 1Gb, 2.5Gb, 5Gb, 10Gb all supported. Oh got 2 of these at £54.00 so bit of a bargain.

Bought two cards for a computer to computer network (between an ESXi host and Mac OS Hackintosh). Hackintosh card started acting up within months, reporting an unplugged cable or an unresponsive device on the other end, dropping packets, and disconnecting SMB/NFS shares. Nothing was changed in the configuration and all problems and troubleshooting point to the faulty card. Found similar experiences with this card on forums online, too. Wouldn't recommend.

This Product overheated and failed. Returned to Amazon for refund.

Only reason I'm knocking off a star at all is the product doesn't explicitly match the advertised photo this time. I've bought two of these previously, and received the version in the photo: half height, quarter length, black PCB. What I received this time was half height, half length, red PCB. So, if you're carefully planning your build's interior aesthetic, you may get a svelte, miniature black card, or you may get a larger, flashy red card. I'm sure I'll find a happy use for it, as I'm really just buying a few extras because the price is good. That said, these Marvell Acquantia AQC107 chips perform just fine, they give me up to 1.09GB/s transfer speeds from my NAS, consistently. Just replace the thermal pad on it prior to deploying, as the stock pad is kind of trash quality and will let the chipset overheat, causing throttling.

I bought this to replace an older AQC108 (5Gbit and lower) card. I was able to connect at 10Gbit pretty much right away without issues, but I noticed that the card's heatsink wasn't getting anywhere near as warm as the slower card. I pulled the heatsink off after carefully removing the spring mounts to find that the heatsink appeared to be attached to the chip with double sided sticky tape (!) and not the normal heat transferring kind. It was clear and balled up like cheap magazine glue. After replacing it with some proper CPU compound, and reinstalling the springs, the heatsink is now so hot it hurts to touch when the card is operation so it's definitely getting much better thermal transfer. I suspect many of the people reporting that the card had died after a couple of months have actually been cooking them to death. If you've got a case with extremely good airflow or a server chassis you're probably okay with the horrible sticky tape but otherwise consider peeling it off and applying some decent CPU heatsink compound. You can release the plastic springs by lightly squeezing the base on the back side of the board and wiggling them out. Be careful: sometimes they shoot out of the board due to the spring.