One of the best features of the traditional desktop PC is its flexibility. On every desktop motherboard you will find a range of different expansion slots. These slots allow you to insert a huge range of expansion cards, from a super-fast graphics card to a card that can control specialized equipment.
Below if a brief list of common slot types which you may come across.
PCI Express (Peripheral Component Interconnect Express)
32 bit slot
PCI Express slots are commonly used for graphics cards. They are available in different sizes each capable of offering more bandwidth. These slots range from x2 to x4, x8, and x16 with the x16 as the most common slot.
PCIe Slot x16
PCIe Slot x1
PCI (Peripheral Component Interconnect)
32 bit / 64bit
The PCI slot has proven to be a very flexible slot, but is slowly becoming less common. Popular PCI expansion cards which you my come across are sound cards, network cards and modems.
AGP (Advanced Graphics Port)
Once a very popular slot designed for advanced 3D graphics, it has been phased out by PCI Express.
EISA was a expansion on ISA and was not common in the desktop market, it became superseded by VESA and PCI.
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ISA (Industry Standard Architecture)
16 bit/8 Bit
ISA was a very popular flexible slot in its time. It offered support for a large range of expansion cards. You will no longer see this slot unless in specialized situations.
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