What PCI Express Means for Network Cards
While the majority of computers already come with networking capabilities, there are times when you might need to add a new network adapter. New cards give you access to new technologies and often bring higher performance.
What's the Difference Between PCI and PCIe?
While you can add an external USB adapter to your computer, you can usually get better performance on a desktop PC if you use expansion cards. These cards fit into slots on the motherboard, giving them a direct connection to the chipset. As with many other computer components, they all only fit into the slot they are designed for to minimize the chances of accidental damage. The two main interfaces found on computer motherboards are PCI and PCI-Express:
- PCI: Peripheral Component Interconnect is a 32-bit parallel interface based on a shared bus architecture. Each card uses a shared connection through a common interface that gives a total bandwidth of 133 MB/sec for all devices.
- PCI-Express: PCI Express is a serial interface, with each slot supporting anywhere from 1 to 16 lanes. This means that every PCIe device has its own dedicated bandwidth. For PCI Express x1 that means a minimum of 1 Gb/sec of total bandwidth from a single connector, which is more than enough for most network adapters.
What Features Should You Look for in a Network Card?
There are actually a few things to consider when looking for a new network adapter for your computer, some of which are obvious while others may be not so obvious:
- Interface: The first thing to consider is the interface. An Intel PCI Express x1 card requires a single lane card of the correct generation in order to see its maximum utility. Each revision of the PCIe specification has maintained the same physical connector but increased bandwidth.
- Speed: You determine the network transfer rate by the speed of the card. For a PCI Express x1 card that usually means Gigabit Ethernet. You can get faster speeds, but the problem is that they would saturate a single lane connector.
- Features: Look for features like wake-on-LAN where the network card can rouse the PC from sleep.
- Ports: Most adapters only offer a single Ethernet port, but some Intel server adapters offer as many as four ports on a single PCIe card. This is more than most people need in a desktop adapter but can be very useful in a server environment.
Upgrading Your Machine
Like a graphics card, a network adapter can easily upgrade if you know what you're doing. The most important things to remember are to always ground yourself and don't force the components. Every card only fits one way, so make sure you're dealing with the right card in the right orientation before pushing too hard.