The Peripheral Component Interconnect, also known as PCI, has been licensed by Intel in the 1990s. The bus is used as a communication lane to transmit signals and data from your computer system to peripheral devices attached to the computer system. Compared to the earlier VL-bus and ISA, it has a higher performance capacity and avoids any risk of interference with your CPU.
How does it work?
The processor is connected to the other components like the hard drives, the main memory and the PCI slots by the use of a front-side bus. The speed of the front side bus can reach up to 400 Mhz with a system operating at the speed of 800 Mhz.
The backside bus usually has a quicker speed than the front-side bus but operates at the same rate as the processor itself. Though it is a detached connection, it ensures the connection between the processor and the Level 2 cache. With time, the level 2 cache was included in the main processor to make them more affordable and easier to use.
Different Bus Types
PCI 32 bits have a bus speed of 33 MHz and operate at 132 MBps
PCI 64 bits have a bus speed of 33 MHz and operate at 264 MBps
PCI 64 bits have a bus speed of 66 MHz and operate at 512 MBps
PCI 64 bits have a bus speed of 66 MHz and operate at 1 GBps.
Advantages of PCI
The PCI technology offers a number of advantages compared to the VL-Bus or ISA.
1. You can connect a maximum of five components to the PCI and you can also replace each of them by fixed devices on the motherboard.
2. You an have multiple PCI buses on the same computer
3. The PCI bus will enhance the speed of the transfers from 33MHz to 133 MHz with a transfer rate of 1 gigabyte per second.
4. The PCI can handle devices using a maximum of 5 volts and the pins used can transfer more that one signal through one pin.