The motherboard hold the CPU, BIOS, Memory, mass storage, connectors, Controllers to control standard peripheral devices such as monitors, keyboards and disk drives. All the chips on the motherboard are called the chipset of the motherboard.
In most PCs you can upgrade the components attached to the motherboard like the graphics cards a new CPU to make it faster like more cored and clocked at a higher speed. You can get motherboards now with usb 3.0 connections on it for faster data transfer speed.
A controller is a device that manages the transfer of data from a computer to a peripheral device and from the peripheral device to the computer like graphics cards, disk drives, monitors, keyboards, printers and mice. All computers come with the necessary controllers for all standard components like I have stated earlier. Controllers are designed to communicate with the computer’s buses and there are three standard bus architectures for PCs the AT bus, PCI, and SCSI.
PC’s have different ports on them they are for printers, keyboards, mice, monitors, disk drives, modems, and printers. All personal computers come with a serial RS-232C port or RS-422 port for connecting modem or mouse and a parallel port for connecting a printer.
There is a battery on the motherboard keeps the BIOS on and the time and date this can run out but not very often needs changing like every 5 years.