Controllers and network cards for servers are expansion cards that manage drives or add network ports to a machine. This category suits IT teams, system builders and small businesses upgrading or repairing existing servers. Most products come from Lenovo and HPE, with further items from SanDisk, ATEN, Promise and OWC.
How to choose a server controller or network card
Card type. A RAID controller combines drives into arrays for speed or redundancy, while a host bus adapter (HBA) simply passes drives through to the operating system. Choose an HBA for software-defined storage such as ZFS, and a RAID controller when you want the card to handle mirroring or parity.
Drive interface. Check whether your drives are SATA, SAS or NVMe, because a controller built for SAS and SATA will not manage NVMe drives in the same way. Also count the drive ports or connectors so the card can serve every bay you plan to use.
Network speed and port type. Gigabit Ethernet is enough for basic file and web services, but virtualisation hosts and backup servers usually benefit from 10 Gb or faster. Decide between RJ45 copper ports and SFP+ or SFP28 cages, since fibre or direct attach cables need matching ports and modules.
Server compatibility. Look at the PCIe generation, the number of lanes and the bracket height, as many servers need low-profile cards. Cards made for ThinkSystem or ProLiant servers are normally tested with those platforms, so match the card to your server generation and model before ordering.
Cache and data protection. Hardware RAID cards often include onboard cache, and some protect it with a battery or flash module so queued writes survive a power cut. This matters for databases and busy file servers, but is less important for simple boot mirrors.
Brands we carry in controllers and network cards
- Lenovo: the largest group in our range, covering adapters designed for ThinkSystem servers and workstations, which helps with firmware and management support.
- HPE: known for Smart Array storage controllers and server network adapters built for ProLiant systems.
- Promise: a storage specialist known for RAID systems and Thunderbolt storage products for creative workstations.
- OWC: focused on Mac and Thunderbolt accessories, storage upgrades and expansion products.
- ATEN: known mainly for KVM switches and remote management hardware used in server rooms.
- SanDisk: best known for flash storage such as SSDs and memory cards.
Frequently asked questions
What is the difference between a RAID controller and an HBA?
A RAID controller builds and manages drive arrays itself, while an HBA presents each drive to the operating system individually. RAID cards suit setups where the hardware should handle redundancy. HBAs suit storage systems that manage disks in software.
Do I need a separate network card in a server?
Not always, as most servers include built-in Ethernet ports. A separate network card makes sense when you need more ports, a faster speed such as 10 Gb, or fibre connections. It is also a quick replacement if an onboard port fails.
Will a server controller work in any server?
Not necessarily. The card needs a free PCIe slot of a suitable size, and some controllers rely on firmware or cables made for specific server models. Check the compatibility list of your server before buying, particularly for Lenovo and HPE cards.
How do I know which drives a controller supports?
The product specification lists the supported interfaces, such as SATA, SAS or NVMe, and the number of drive connections. Match these to your drives and backplane. If you are unsure, compare the controller model with your server documentation.
