PCI USB Computer Port Expansion Cards

How to Add More USB Ports to Your Desktop

One advantage of the PC architecture is its expandability. Ever since its inception, it has been built around the idea of increasing capabilities by adding expansion cards and USB is no exception.

Are All PCI Cards the Same?

While people may refer to all expansion cards with the general term "PCI cards" there are actually three different interfaces that fall under the name Peripheral Component Interconnect.

  • PCI: The initial standard referred to a shared topology, providing a 33 MHz connection on a 32-bit shared bus for a maximum bandwidth of 133 MB/sec. While fine for USB 1.0 ports, it did not provide enough bandwidth for multiple high speed ports.
  • PCI-X: The X stands for extended, and refers to the fact that this interface increased both the frequency and the bus width, enabling a 64-bit bus and speeds from 66 to 133 MHz. Also, a shared bus topology it suffered from performance degradation whenever more than one card was on the same bus.
  • PCI-E: PCI-Express is a wholly different serial architecture, basing around dedicated connections, or lanes. PCIe is not only faster than previous standards its also much better able to handle multiple devices as it doesnt require devices to share bandwidth. It has replaced both previous standards and is the only one able to handle SuperSpeed USB.

How Do You Use an Expansion Card?

While some motherboards have internal ports that can be accessed by using a USB header, most offer one or more PCIe slots to provide expansion capabilities. Before installing a PCI Express card there are a few things that you may want to consider:

  • USB Port Types: While most computers already have USB-A ports, a PCIe card may give you the ability to add USB-C compatibility to work with newer devices.
  • Other Ports: Some cards not only support USB, but also offer additional SATA ports, including SATA power for external devices.
  • PCI-E Lanes: While most cards only require 1 PCI Express lane and thus a 1x Slot, some combo cards require a minimum of a 4x slot as they use 1 PCI Express lanes. In some cases, this may require using a larger slot designed for a graphics card, but it does enable a higher data transfer rate than would be possible with PCI-E 1x.

Why Add USB?

The primary reason for adding more USB capacity is to use peripherals. USB is common for all sorts of external accessories, from printers and hard drives to monitors. One thing you should make sure is that you have the right drivers for your card as not even Windows 10 ships with the right PCI-Express chipset drivers for all cards.