How to Identify a PCI-E Slot

Peripheral Component Interconnect Express (PCI-E or PCIe) is the latest in a long line of computer bus standards. PCIe describes the physical slot on the computer motherboard, as well as the technology behind the slot. While PCIe shares a name with the older PCI standard, the two technologies are completely incompatible. If you have a PCIe card and need to install it, or if you are just wondering what kind of expansion cards you can use, you will need to be able to tell a PCIe slot from a regular PCI slot, a PCI-X slot and an AGP slot.

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Instructions

- 1
  
  Open the case that holds your computer's motherboard. Most cases are held together by between one and three screws along the back or bottom, but some cases may have a latching mechanism instead. Consult your computer's documentation for specific instructions on how to open the case to access your expansion ports.
- 2
  
  Find the expansion slots on the motherboard. They will be located near the back of the computer, just a few inches away from the long openings in the back of the computer.
- 3
  
  Look for a slot that has two distinct sections. One small section, which contains 11 pins on each side, is located near the edge of the motherboard, with another section directly behind the first. This second section can be smaller than the first, or much larger, depending on the type of PCI-E port it is. By comparison, a normal PCI slot will have a large section close to the edge of the motherboard, and a small section behind the first section. A PCI-X slot will look like a PCI-E slot, but it will have a third large section behind the second section. Finally, an AGP slot will look similar to an PCI slot, but it will be offset closer to the center of the motherboard.
- 4
  
  Count the pin holes on the second section of the PCI-E slot to determine what kind of slot it is. A PCI-E x1 slot has seven holes, while a PCI-E x4 has 21 holes. A PCI-E x8 has 38 holes and a PCI-E x16 has 71.