HP 10Gb Dual SFP+ Network Card & Hyper-V

HP 10Gb Dual SFP+ Network Card & Hyper-V

When I first started to upgrade my home lab server network to 10Gb, I was determined to do it on a sensible budget. As all of my networking infrastructure is Unifi kit, I bought a 16-port 10Gb switch – this cost around £400 – so I had a limited budget for the rest of the upgrade.

In the end, as with many people upgrading to 10Gb, I decided to buy 2nd-hand network cards from eBay. A couple of minutes later, I found the HP NC523SFP network card. I picked up 10 cards from various eBay suppliers, each costing between £15 and £20.


The NC523SFP is an eight-lane (x8) PCI Express (PCIe) 10 Gigabit network solution offering superior bandwidth in an Ethernet adapter. This dual-port PCI Express Gen 2 adapter supports SFP+ (Small Form-factor Pluggable) connectors, requiring either Direct Attach Cable (DAC) for copper environments or fibre transceivers and fibre cables for fibre optic environments.

The NC523SFP ships with advanced server features that customers have come to expect, such as support for TCP checksum and segmentation (LSO) offload capability, VLAN tagging, jumbo frames, IPv6, and more. Flexible to order and install, the NC523SFP can be used in either standard or low-profile slots.


The great thing about this card is that it is supported out-of-the-box in TrueNAS, Proxmox and has drivers for virtually every operating system out there.

The two ports can also be bonded together to provide extra bandwidth if needed – this is a feature that ensures my TrueNAS server can be used even when it is receiving large VM backups from my servers.

Heat – it’s a hot one

One thing that really surprised me was the amount of heat the cards give off. Running at 10Gb means the cards’ chips get very hot – there is a heatsink on the cards but no fan.

As this is an enterprise card, it is designed to be installed in servers with plenty of airflow. It runs fine in servers with fans blowing air across it, but when I installed it in my Windows 11 machine, it kept losing network connectivity. At first, I thought the card was faulty, so I swapped it out with another one. This ran fine for a few minutes, and then it, too, stopped working. When I pulled the card out of the machine, I burnt my fingers and then the penny dropped. It needed air moving over the heatsink.

I jerry-rigged a fan onto the card, and it has functioned without a problem since.


Drivers for the card can be found here: –


Installing the driver on Hyper-V

The normal Windows driver cannot be installed using the executable, but you can extract the driver and then install it with this command: –

Pnputil -i -a qlnd6x64.inf

Hi, my name is Stephen Finchett. I have been a software engineer for over 30 years and worked on complex, business critical, multi-user systems for all of my career. For the last 15 years, I have been concentrating on web based solutions using the Microsoft Stack including ASP.Net, C#, TypeScript, SQL Server and running everything at scale within Kubernetes.