Why do different types of IO devices require different slots

Why do different types of I/O devices require different slots?

Solution

All motherboards have one or additional system I/O buses that are accustomed expand the computer\'s capabilities. The slots within the back of the machine are wherever enlargement cards are placed. These slots permit you to expand the capabilities of your machine in many various ways in which, and therefore the proliferation of each general purpose and really specific enlargement cards is a component of the success story of the laptop platform. Most modern PCs have 2 differing kinds of bus slots. The primary is that the commonplace ISA slot; most PCs have three or four of those. These slots have 2 connected sections and begin a few half-inch from the rear of the motherboard, extending to around its middle. This can be the oldest bus kind and is employed for cards that do not need plenty of speed: for instance, sound cards and modems. Older systems might have ISA slots with solely one connecter piece on each; these are 8-bit ISA slots and can solely support 8-bit ISA cards. Pentium systems and newer 486-class motherboards even have PCI bus slots, again, typically three or four. They’re distinguished from ISA slots in 2 ways in which. First, they\'re shorter, and second, they\'re offset from the rear fringe of the motherboard by concerning an in... PCI may be a high-speed bus used for devices like video cards, fixed disk controllers, and high-speed network cards. The newest PCs add another, new connecter to the motherboard: associate degree Accelerated Graphics Port slot. AGP isn\'t very a bus, however may be a single-device port used for superior graphics. The AGP slot appearance the same as a PCI slot, except that it\'s offset away from the rear fringe of the motherboard. Older 486 systems use VESA native Bus, or VLB slots rather than PCI to attach high-speed devices. This can be associate degree older bus that began to be abandoned in favor of PCI at round the time the Pentium was introduced. VLB slots seem like ISA slots; solely they add third and fourth sections on the far side the primary 2. This makes their connectors terribly long, and for that reason VLB cards are notoriously tough to insert into or take away from the motherboard. Care should be exercised to avoid injury. Some motherboards incorporate an alleged \"shared\" ISA and PCI slot. This name implies one slot that may take either kind of card, however that may not potential as a result of the 2 slot sorts are physically incompatible. so as to save lots of house whereas maximizing the amount of enlargement slots, some designers place associate degree ISA slot on the board right next to a PCI slot; you then have the selection to use either the ISA or the PCI slot, however not each. This style is feasible as a result of ISA cards mount on the left-hand facet of a slot position, whereas PCI slots mount on the right-hand facet.