Desktop & Server Serial Cards - PCI Express

PCIe Spec

PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe (or PCI-E, as it is commonly called), is a computer expansion card standard designed to replace the older PCI, PCI-X, and AGP standards. PCIe 2.1 is the latest standard for expansion cards that is available on mainstream personal computers.

PCI Express is used in consumer, server, and industrial applications, as a motherboard-level interconnect (to link motherboard-mounted peripherals) and as an expansion card interface for add-in boards. A key difference between PCIe and earlier buses is a topology based on point-to-point serial links, rather than a shared parallel bus architecture.

PCI and PCI Express Comparison

	PCI	Universal PCI	PCI Express
Brainboxes Range
	CC	UC	PX
Slot Compatibility	Only 1 Key Way: Can only be inserted in 5V PCI slots	2 Key Ways: Can be inserted in either 3.3V or 5V PCI slots	Can be inserted into ANY PCIe slot (x1,x2,x4,x8,x16)
Height	PCI Express boards are the same height and length as PCI cards
Bracket	PCI Express uses the same card brackets as PCI boards, either standard or Low Profile

Low Profile and Standard Height

Both PCI and PCIe cards can come in different heights. The height effects which kind of computer the card can fit into. Low Profile (or half height or low height) fit into slim PC's and servers. A general rule of thumb is that if the height of your PC (including case) is less than 4 inches ( 100mm) then it requires a low profile card.