TIPS-3

PCB (Printed Circuit Board):
The foundation of every electronic device is the board on which every component is connected. The PCB consists of minute conductors, usually of copper, seen as fine lines criss-crossing the surface, mounted on an insulated substrate. The minute pathways actually carry data signals or power between the various components that are eventually soldered on the PCB. PCBs come in various sizes and shapes, and besides the motherboard, are also seen in expansion cards (sound cards, graphics cards, etc.) and RAM modules.

PCI:
Peripheral Component Interconnect is still widely seen in motherboards, though it is older than AGP. The wide availability of PCI cards is one reason for this. This bus is 32 bits wide and operates at 33 MHz, and has a maximum data transfer speed of 132 Megabytes per second. This bandwidth is divided between all slots and also the storage devices, like the hard disks.

PCIE (PCI-Express):
PCI-Express is the latest type of expansion slot. Unlike the AGP and PCI buses which transfer data in a parallel fashion, PCIE offers serial data transfer. It is designed to be a point-to-point bus, and so it is not shared by other components.

Ports:
Every motherboard offers a plethora of ports on its back panel. The most commonly seen ports on today's PCs are PS2, USB, VGA, LAN, Serial, and Audio Sockets.

PS2 port:
The PS2 port is used to connect PS2-compatible keyboard and mouse. The violet-coloured port is usually for the keyboard, and the green one is for the mouse.

RAM slots:
These refer to the interface to connect RAM modules. Memory is organised in the form of banks, with one or more slots constituting a bank. Each bank has a dedicated channel to the memory controller.

Serial port:
DB 9 or Serial port is a 9-pin port that transfers data serially. It is increasingly being left out from the back panel in favour of faster ports like USB. It is used today mostly for external modems.