The motherboard is considered as the main circuit of the computer, it contains the connectors for attaching additional boards. Typically, the motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and parallel ports, expansion slots, and all the controllers required to control standard peripheral devices, such as the display screen, keyboard, and disk drive. Collectively, all these chips that reside on the motherboard are known as the motherboard's chipset. You must familiarize the motherboard parts and its function since this is needed to pass the TESDA NC II Computer Servicing Exam.
Parts of the Mother Board
A main function of the BIOS is to give instructions for the power-on self test (POST).This self test ensures that the computer has all of the necessary parts and functionality needed to successfully start itself, such as use of memory, a keyboard and other parts. If errors are detected during the test, the BIOS instruct the computer to give a code that reveals the problem. Computer Error codes are typically a series of beeps heard shortly after startup.
Carbon Metal–Oxide–Semiconductor (CMOS) - is a technology for making integrated circuits. CMOS technology is used in microprocessors, microcontrollers, static RAM, and other digital logic circuits. CMOS technology is also used for a wide variety of analog circuits such as image sensors, data converters, and highly integrated transceivers for many types of communication. Frank Wanlass successfully patented CMOS in 1967 (US Patent 3,356,858).
- Is a button cell battery that gives power to CMOS so that the Bios setting is
retain when the PC is turn off.
Chipset - Refers to a specific pair of chips on the motherboard: the NORTHBRIDGE and the SOUTHBRIDGE.The northbridge links the CPU to very high-speed devices, especially main memory and graphics controllers.
connects to lower-speed peripheral buses (such as PCI or ISA). In many modern
chipsets, the southbridge
actually contains some on-chip integrated peripherals, such as Ethernet, USB,
and audio devices. A chipset is usually designed to work with a specific family
of microprocessors. Because it controls communications between the processor
and external devices, the chipset plays a crucial role in determining system
Types of Processor Sockets or Slots
|PGA Processor Slot|
Types of Memory Socket or Slot
Memory Socket or Slot - is commonly refers to the slot in a motherboard were the extended memory modules are installed.
|SIMM (Single-inline-memory module) slot, 72 pins|
|DIMM (Dual-inline-memory modules) slot. SDR (Single Data Rate) DIMM slot. 168 edge contacts.|
|DDR (Dual/Double Data Rate) DIMM slot. 184 edge contacts (DDR 1)|
|DDR (Dual/Double Data Rate) DIMM slot. 240 edge contacts (DDR 2 / 3)|
SODIMM (SO-DIMM is short for Small Outline DIMM ) Slot A 72-pin and 144-pin configuration. SO-DIMMs are commonly utilized in laptop computers.
Computer System Expansion Slots
The Expansion slot is a type of slot that connects an expansion bus (Adapter card), which allows the processor to communicate with peripheral attached to the adapter card. Data is transmitted to the memory or the processor travels from the expansion slot via the expansion bus and the system bus.
|PCI - Slot|
|AGP - Slot|
AMR SLOT - Audio Modem Riser, Is a riser card that supports sound or modem function.
ACR SLOT - Advance Communication Riser, this type of slot is for communication and audio subsystem. The slot supports modem, audio, LAN, and Home Phoneline Networking Alliance (HPNA) or Home Networking cards.
CNR SLOT - Communications network riser, this connector supports specially designed network, audio, or modem riser cards, main processing is done through software and controlled by the motherboard’s system chipset.
|PCI - Express|
- PCIe 1.1 (the most common version as of 2007) each lane carries 250 MB/s.
- PCIe 2.0 doubles the bus standard's bandwidth from 2.5 Gbit/s to 5 Gbit/s, meaning a x32 connector can transfer data at up to 16 GB/s in each direction.
- PCI Express 3.0 will carry a bit rate of 8 giga transfers per second.
|IDE - Controller|
|FDD - Controller|
|SATA - Controller|
- SATA 1.5 Gbit/s
- SATA 3.0 Gbit/s
- SATA 6.0 Gbit/s
Types of Power Supply Terminal
|ATX - Power Connector|
These connectors are for power supply, the power supply plugs are designed to fit these connectors in only one orientation.
- AT / ATX
- Auxiliary power
FRONT PANEL CONNECTOR / SYSTEM PANEL CONNECTOR - This connector attaches the switches and indicators.
- Power switch (PWRSW) power-on the system unit
- Reset switch (RESET) – Resets the system unit
- Power / System LED – The system power LED lights up when system is powered up / Power indicator
- Hard disk drive LED (HDDLED) –The HDD LED lights up(Blinks) during harddisk activity.
INPUT/OUTPUT (I/O) PORTS
I/O Ports are type of interface which a peripheral attaches to or communicates with the system unit so the peripheral can send data to or receive information from the computer.
- Keyboard / mouse
- Monitors, projector
- Printers, flatbed scanner
- External storage devices, external modems
- Headsets, microphones, game pads
USB PORT - Universal Serial Bus, a 4-pin serial cable bus that allows up to 127 plug-n-play computer peripherals. This allows attaching or detaching of peripherals while the host is in operation. Supports synchronous and asynchronous transfer types over the same set of wires up to 12Mbit/sec. USB 2.0 provides 40 times the transfer rate compared to USB 1.0 and competes with the 1394 standard.As of today we now have USB 3.0.
GAME/MIDI PORT - This connector supports a Joystick or a Game Pad for playing games, and MIDI Devices for playing or editing audio files.