Refurbished Network Cards

Buy used network cards for servers at low prices and save money

When configuring a server, the focus is usually on the processor, RAM modules or internal memory. However, components such as network cards also play a key role, as they determine the speed, stability and flexibility of data transmission. And this is essential in view of the rapidly growing digital requirements in many companies.

However, professional-grade hardware is often difficult to finance, especially for small businesses or SMEs with limited budgets. Yet devices from well-known manufacturers that are technically up to date do not have to be expensive: the ‘magic word’ is refurbished.

As with the purchase of used servers, it is worth investing in used network cards. As an attractive alternative to new products, they are on a par with them in terms of quality and durability – but at a much lower price. Used NICs often come from professional server environments, such as lease returns from large companies.

All devices that we purchase and refurbish for a second life are checked in our in-house technical centre for both visual and technical integrity before they are put back on sale. This means you can be sure that you are receiving only flawless hardware that you can use to reliably expand your existing systems.

The advantages of used server adapters are obvious: they are significantly cheaper than new server components, readily available on the market and tested by IT professionals like us. In addition, many companies are increasingly turning to sustainable used goods. This is because the use of refurbished servers and server components reduces the disposal rate and at the same time conserves valuable resources that would be used in new production.

Choosing the right design: full height, half height or mezzanine cards

Our wide and comprehensive range includes a large selection of all types of hardware. In addition to servers, storage and network devices, we also offer numerous components for these. This includes a wide range of different server NICs (= ‘network interface cards’) and PCIe expansion cards, e.g. with full height (full profile slot bracket), half height (low profile slot bracket) or (for blade servers) as mezzanine cards.

In addition to RJ-45 network cards (with classic Ethernet connection) as 1GB or 10GB RJ45 variants, you will also find powerful SFP+ NICs and state-of-the-art 40G QSFP+ adapters for maximum bandwidth in our server shop. Special solutions such as InfiniBand NICs, FibreChannel NICs (FC NICs) and matching transceiver modules (Gbics) are also available – always tested and ready for use.

When purchasing, it is important to consider a few things in advance, as with all server components. If you want to buy network cards, you first need to know which design is compatible with your existing system. This depends heavily on the server type, the chassis format and the available expansion slots. The choice between full profile or half profile plug-in cards and mezzanine adapters is not only a question of space, but also of functionality and compatibility.

Full-height LAN cards (i.e. with a ‘long slot bracket’) are considered the classic standard size for servers and workstations. To find out which slot height you need, a quick look at the back of the server is usually sufficient. If the dummy bezels (or installation slots) measure only approx. 8 cm, an adapter with a low-profile bezel is required; if the slots are approx. 12 cm in size, you will most likely need plug-in cards with a full-profile slot bracket. You can also use the part or device number to check the respective manufacturer's data sheet to see which and how many installation slots the server has for PCIe adapters.

Mezzanine cards, on the other hand, were developed specifically for blade servers or modular server systems. These adapters are not plugged into classic PCI Express slots, but directly onto the motherboard or designated intermediate levels. It is therefore particularly important to check whether the intended plug-in card is compatible with the existing system. Compatibility varies not only from manufacturer to manufacturer, but also between server generations and models.

An often overlooked aspect: accessories also play a role. In addition to the slot bracket, it is also important to check whether suitable cables or modules need to be installed. For SFP adapters, these are, for example, suitable transceiver modules, and for RAID controllers or SAS expanders, these are, for example, SAS cables or backplane accessories.

From architecture to connection: Which interfaces are crucial?

The design of the expansion card is one thing, but of course it also depends on the requirements placed on the adapter. In modern networks, these can be as varied as the areas of application themselves and depend heavily on the existing IT infrastructure. It is therefore essential to check which ports the network and switch support.

Functional requirements & interfaces

• RJ45 network cards

  The RJ-45 adapter is the component of a server that allows it to connect to the network. Since several networks (e.g. Internet, local company networks) may be used redundantly or separately from each other, additional RJ-45 ports are required. Onboard cards often do not offer sufficient connections and usually only provide a speed of 1 Gbit/s. For a faster connection (e.g. 10 Gbit/s), dedicated network cards with LAN ports are therefore required.

  These network cards are typically used in Ethernet-based networks and connected via copper cables (twisted pair cables, e.g. Cat6, Cat7 or Cat8). In addition to the appropriate PCIe slot type(e.g. x4 or x8), you should also check whether you need the low profile or full profile version of the adapter and whether it is compatible with your operating system (e.g. Linux, VMware).

  Common RJ-45 network cards include the Intel i350 -T4 adapter with 1 Gbit/s and 4x RJ-45 ports, the HPE 561-T dual-port adapter with 10 Gbit/s, which is optimised for HPE ProLiant servers, or the Intel X540-T2 adapter with 2x RJ-45 ports and 10 Gbit/s data transfer.

• SFP+ network cards

  If you need a connection via fibre optic cable (or special copper cables) and very fast data transfer over long distances, you should use network cards with SFP+ ports. Using interchangeable GBIC modules that are plugged into the ports of the SFP+ adapter, you can establish the desired connection as needed. SFP+ NICs are mostly used in data centres, redundant or virtual networks and SAN systems that require high bandwidths and where flexibility and speed are key.

  SFP+ supports transmission rates of 10G, 16G SFP+ or even 40G QSFP+, which means enormous bandwidth with minimal latency. The modular pluggable transceivers can support different wavelengths, distances or cable types – including multimode and singlemode fibre optic cables as well as Direct Attach Copper (DAC) for short distances.

• InfiniBand network cards

  InfiniBand NICs are considered a ‘special solution’ for particularly demanding network environments. This is because they are characterised by extremely low latencies at high throughput rates, making them ideal for high-performance computers, cluster systems or specialised applications (e.g. AI, machine learning or big data analysis).

  InfiniBand adapters often support RDMA (Remote Direct Memory Access), which enables direct, efficient memory access without CPU load. Another advantage is that, unlike Ethernet, InfiniBand uses a fabric network with parallel data paths, thus cleverly avoiding bottlenecks.

• Mezzanine network cards for server blades

  Mezzanine cards or blade adapters feature a particularly space-saving design. These plug-in cards were developed specifically for blade server systems and are plugged directly into the blade's motherboard to modularly expand network, storage or I/O functionality.

  It is particularly important to pay attention to compatibility here. This is because the adapter must not only be compatible with the manufacturer and server model, but also with the respective generation or, more precisely, the motherboard. Mezzanine cards communicate with the blade chassis and its switch modules via dedicated backplane connections – without external cabling. This means that they are not only perfectly adapted to limited space conditions, but also feature simple management. Depending on the application for which the plug-in card is required, various versions are available that support Ethernet, Fibre Channel or InfiniBand protocols, for example.

As you can see, choosing the right expansion card for servers depends largely on the intended use. While RJ-45 serves as the ‘standard office communication medium,’ SFP+ and InfiniBand plug-in cards offer special advantages – especially in performance-critical scenarios. But of course, it is important to consider which protocols and ports are supported by the existing network and switch. To make the choice easier and help you with your considerations, we have created a short FAQ:

FAQ: Network cards & interfaces

That depends on the intended use and the existing network infrastructure. In general, however, RJ-45 (Ethernet) is ideal for classic office communication and simple networks. Fibre Channel (FC) is often used for high-availability storage networks. SFP+ or QSFP+ offer high bandwidths and are therefore perfect for data centres or virtualised environments. If extremely low latencies and high throughput are required (e.g. HPC, AI or big data), InfiniBand offers the optimal solution.

Here, too, the direct application scenario is decisive. For simple data transfers, standard office applications and classic LAN connections, 1 Gbit/s (Gigabit Ethernet) is sufficient. If larger amounts of data need to be moved, such as in virtualised environments, demanding workloads, a backup server or larger databases, 10 Gbit/s (SFP+ or RJ-45) makes more sense. For high-performance computing, AI applications, cloud platforms, big data and storage networks with extremely high data volumes, where maximum speed is crucial, 25G, 40G or 100G QSFP+ or SFP28 connections will be necessary. And, of course, the network card should not only be compatible in terms of speed, but also with the rest of the infrastructure (switches, cables, protocols).

The question here is: maximum stability and range or a simple, cost-effective and efficient solution? Electrical (RJ-45) is much cheaper, but it is also more susceptible to interference and limited to a certain range. Optical transmission (such as SFP+ or Fibre Channel) achieves greater ranges, but this option is also more expensive. For shorter distances within a rack or office, RJ-45 connections are therefore more cost-effective and ideally suited. If structured cabling across multiple rooms is necessary (e.g. in data centres), energy-efficient, long-range SFP+ or FC connections are a sensible choice.

If a network card is required for virtual servers or remote management, the following factors are particularly important:
SR-IOV: Provides direct access to VMs, which improves latency and overall performance.
VLAN tagging: To logically separate networks and thus ensure a higher level of security.
Wake-on-LAN: Ideal for centralised administration and remote management.
TCP/IP Offloading: To shift protocol processing and reduce the load on the CPU(s).

Of course, that depends on the intended use and the card itself. Used network cards should generally only be purchased from professional refurbishers to ensure that they have been tested and reconditioned. The argument that used network cards are outdated is not true – because, depending on returns from leasing companies, even very new server adapters can come onto the market. It is important to know which plug-in card you need and to only purchase it from reputable suppliers.

Advanced connectivity: What advantages do network cards offer for servers in general?

Reliability, security, stability and speed are considered key requirements for internal IT infrastructure. Particular attention is paid to server communication – both with internal and external systems. This is exactly where network cards come into play: as an interface between hardware and network, they ensure that data is transferred securely and at maximum speed, improve performance and cleverly reduce bottlenecks.

Onboard cards are usually not sufficient for this, which is why many rely on additional network cards that offer significantly higher transfer rates (e.g. 10G / 40G). In addition, upgrading with a special network card often allows certain protocols to be used and enables the server to manage multiple network connections simultaneously and independently. This allows management functions and data traffic to be separated, for example, which ensures greater security and efficiency.

Server plug-in cards (e.g. NIC RJ-45 or SFP+) therefore not only offer a higher degree of connectivity, but also maximum flexibility. They can be used to make targeted enhancements that are precisely tailored to the requirements of the respective network. Whether for virtualisation, data backup, increased speed or clustering: with the right network card, you can create a powerful and future-proof infrastructure.

Network card vs. host bus adapter: two technologies, one common goal

NIC or HBA – which do I actually need? Both adapters enable a server to communicate with external systems – however, there are significant differences in terms of the function and area of application of the adapters:

As is already known, NIC stands for network interface card. It is the link between the server and the network (e.g. Internet, local company network). Data can be exchanged via the network card, including sending emails or providing websites. Typical interfaces are Ethernet (RJ-45), Fibre Channel or InfiniBand to establish a connection to the LAN, VLAN or WAN. NICs are also indispensable for direct point-to-point communication or management networks.

Unlike network cards, host bus adapters are specialised in data exchange with storage solutions, such as SAN or NAS systems. HBAs primarily support protocols such as Fibre Channel or SAS and operate directly at the block level – i.e. where data is physically written and read. HBAs are therefore used where data is not stored on the servers themselves, but on high-performance storage solutions, backup systems or in virtualised environments. Data transmission also reveals a key difference between NICs and HBAs: while network cards usually work at the file or packet level and send and receive data packets via network protocols such as TCP/IP, HBAs communicate directly with the storage systems. This often works via Fibre Channel protocols, which enable access to the physical storage sectors. Here is a brief overview:

Comparison of NIC & HBA

Network cards and HBAs are not the same – they perform different tasks and have their own technical characteristics. However, both plug-in cards ensure a powerful, stable and scalable IT infrastructure.

This makes it all the more important to choose high-quality professional hardware when selecting server components. Refurbished hardware is a sustainable, cost-effective and smart choice, as it allows you to implement a high-performance IT infrastructure at a low price.