Introduction:
Hey guys, been a forum member for some time now and had a lot to learn from you guys. This is just my feeble attempt at trying to write my first “Walkthrough†. I have written about motherboards because there many online guides which tell you about specific things on the board but having all the info at one page is sometimes difficult to find.
I have tried to focus some of the more discussed features of the motherboard like layout, main components, functioning of each component and other features which are less frequently covered such as form factors, capacitors, jumpers etc.
So Here it goes:
The Motherboard is considered to be the most under-rated component while building a new system. Most new enthusiast buyers concentrate on other important components like CPU and Graphics cards but give little thought to the motherboard, which is equally important and is one of the critical components of a system. Motherboard, also called as Mainboard, (board, mb or mobo) is the core mechanism of a modern computer system. It is a PCB (Printed Circuit Board) which is designed to control and co-ordinate between all other system components like CPU, RAM,I/O, Graphics Cards, Sound etc.
Form Factor:
Modern motherboards can be broadly classified on the basis of their form factors. The form factor defines the size and the physical design of the motherboard. it specifies the arrangement of different system components such as the CPU socket ,PCI Slots, DIMM channels etc. It also mentions the specifications of the cases and power supplies that can be used in combination with the motherboard. two motherboards can offer same features and perform same functions but can be of different form factors. Some of the main form factors are ATX ,BTX, Micro-ATX, Mini-ITX etc.
Motherboards can also be classified by other standards such as:
1)The Socket for the microprocessor which determines what kind of Central Processing Unit (CPU) the motherboard uses. The processor socket is the connector on the motherboard that houses a CPU and forms the electrical interface and contact with the CPU. Processor sockets use a Pin Grid Array (PGA) where pins on the underside of the processor connect to holes in the processor socket. Examples: Socket 775,Socket 1366 etc.
[BREAK=Layout]
Layout:
The most common layout in modern motherboards is described by the Standard ATX form factor . Following is a layout diagram of ASUS P5Q PRO with every component tagged and named.
Chipset:
The chipset is the nervous system of the motherboard. It is a collection of different chips where the logic to control the functioning of the motherboard resides. Whatever information is passed to the CPU, RAM etc to process, it cannot proceed further without passing through the chipset.
The chipset is usually made of two parts: the Northbridge and the Southbridge. These two bridges connect the CPU to other parts of the computer such as the DRAM slots or the I/O devices.
Chipsets are optimized by manufacturers to work with specific CPUs. The chipset is an integrated part of the motherboard, so it cannot be removed or upgraded. This means that not only must the motherboard's socket fit the CPU, the motherboard's chipset must work optimally with the CPU. Examples of chipsets are P35,P45,x48,x58 etc (for Intel boards) and 680i,750i etc(for nForce boards)
Basic Layout of a Chipset:
Northbridge:
The Northbridge can be thought of as the “Big Daddy†of all components on the motherboard. The traditional Northbridge handles the communication between the CPU,RAM,AGP or PCI Express and the Southbridge. It plays a major part in defining the specifications such as maximum speed of CPU, number of CPUs on the board, the maximum amount of Memory (RAM) that can be accommodated on the board. Other factors such as voltage regulation and available number of connectors also play a role. The Northbridge also contains integrated graphics controllers on motherboards which have included them on the board itself. Since the Northbridge is clearly predefined to work with particular devices, one type of Northbridge only supports one particular technology in a device. Exceptions are made to this mechanism during the transition period between two technologies such as DDR2 to DDR3 RAM or the 65nm to 45nm CPU chips.
Similarly, one Northbridge will only work with one or two different Southbridges, which brings upon limitations on the functioning of the technologies which are available to the Southbridge.
Traditional Northbridge based on Intel’s P45 chipset:
The Traditional Northbridge may become obsolete in the coming years; new designs are being made to overcome the problems and hurdles in the traditional Northbridge. In AMD64 processors, the memory controller, which handles communication between the CPU and RAM, has been moved onto the processor itself. This method significantly reduces the communication delay caused in the traditional Northbridge . Also, AGP graphics cards are becoming obsolete by rapidly being replaced by PCI Express cards. This will render one of the main features of the Northbridge (communication with AGP slots) useless.
AMD’s 790FX chipset where the Memory Controller is directly built into the processor:
Front Side Bus (FSB):
The Front Side Bus (FSB) is a bi-directional data bus on the motherboard that connects the processor (CPU) to the Northbridge. This data bus is used to transfer data (in form of information signals) from the CPU to the Northbridge. The frequency at which a processor (CPU) operates is determined by applying a clock multiplier to the front side bus (FSB) speed. For example, a processor running at 2400 MHz might be using a 266 MHz FSB. This means there is an internal clock multiplier setting (also called bus/core ratio) of 9; the CPU is set to run at 9 times frequency of the front side bus: 266 MHz x 9 = 2400 MHz .By varying either the FSB or the multiplier, different CPU speeds can be achieved. The front side bus has been a part of computer architecture since applications first started using more memory than a CPU could reasonably hold.
There is also another bus on some motherboards called the Back Side Bus which connects the external L1 and L2 cache to the CPU. This access of data is much faster that accessing the RAM through the FSB although the size is significantly lower than RAM.
[BREAK=Southbridge]
Southbridge:
Secondary Super I/O Controller:
[BREAK=Southbridge]
Southbridge:
The Southbridge can be thought of as the Second-in-Command on the motherboard after the Northbridge. All the functions which do not require direct interaction with the Northbridge components are connected to the south bridge. Since Southbridge is located farther away from the CPU than the Northbridge, there is a small amount of delay in the information reaching the processor compared to Northbridge. This delay in communication does not affect the smooth functioning of the chipset because all the southbridge functions mainly deal with Input/output and are not as critical as the northbridge functions to the chipset.
The Southbridge is in charge of functions including the PCI, the PS/2 interface for keyboard and mouse, the serial port, the parallel port, and the floppy drive controller. Some southbridges implement additional features such as a RAID controller or an integrated sound card. In modern systems, the southbridge is also in charge of the parallel ATA interface (PATA) ,the serial ATA interface (SATA),ETHERNET,USB and FIREWIRE.
One Southbridge can be paired with Northbridges on a chipset but the combination must be designed to work together by the manufacturer.
Some of these functions are often handled by a secondary I/O controller, and in that case the southbridge provides an interface to this chip.
The Intel ICH10R Southbridge:
The Super I/O controller is a chip designed especially for interaction of low-bandwidth I/O devices with the Southbridge. These devices include: The I/O chip is integrated in the Motherboard itself.
CMOS:
Jumpers:
[BREAK=Capacitors]
Capacitors:
Solid State Capacitors:
Thanks guys for bearing with me. I know the images are edited badly but i have done the best i could
.Please Leave a comment on how i have written/compiled this walkthrough. Thanks Again
- Floppy disk Controller
- Parallel Port (Used for Printers)
-Keyboard and Mouse Interface
-Serial Ports
The Back Panel of the Motherboard where the Super I/O devices have their output connectors:
[BREAK=CMOS and Jumpers]
CMOS:
CMOS is short for Complementary Metal-Oxide Semiconductor .It is a type of non-volatile memory used for storing the system time and the system settings for your computer configuration. It is powered by a lithium battery called the CMOS Battery. The standard lifetime of a CMOS battery is around 10 Years. However, this amount of time can change depending on the use and environment that the computer resides.
Jumpers:
A jumper is two or more connecting points that can be conveniently shorted together. Jumper pins (points to be connected by the jumper) are arranged in groups called jumper blocks, each group having at least one pair of contact points and often more. Sometimes these groups are referred to as headers. In general, each contact in a jumper block terminates in a small metal pin.
Capacitors:
A capacitor is a mini battery or charge storage, so some components rely on them when you cut power to the computer. They are used a lot when certain components need a clean steady source of power too; They clean up power (spikes, sound etc.)
On the motherboard is a set of components known as the "VRM" (voltage regulator module). They produce the power supply for the CPU itself, which is typically around 1.5 volts for a modern CPU(Which is also call VID or Voltage Identification Data).They do this by letting small pulses from the 12 volt supply into a bank of capacitors through several coils. If the voltage drops below the CPU’s VID, they let more pulses through. If it rises above it, they let fewer pulses through. This provides a smooth, regulated voltage to the CPU. The capacitors are kind of like the gas tank in your car. The CPU empties it by using power stored there. The pulses stop it from getting too empty.
Electrolytic Capacitor:
There’s a certain type of capacitor called an electrolytic capacitor that uses an electrolyte between the electrodes or plates in order to increase its capacitance.They are valuable in relatively high-current and low-frequency electrical circuits. This is especially the case in power-supply filters, where they store charge needed to moderate output voltage and current fluctuations in rectifier output.
Capacitor Plague:
An incorrect electrolyte formula within a faulty capacitor causes the production of hydrogen gas, leading to bulging or deformation of the capacitor's case, and eventual venting of the electrolyte. In rare cases, the faulty capacitors have even been reported to pop or explode forcefully.
Electrolytic Capacitor:
There’s a certain type of capacitor called an electrolytic capacitor that uses an electrolyte between the electrodes or plates in order to increase its capacitance.They are valuable in relatively high-current and low-frequency electrical circuits. This is especially the case in power-supply filters, where they store charge needed to moderate output voltage and current fluctuations in rectifier output.
Capacitor Plague:
An incorrect electrolyte formula within a faulty capacitor causes the production of hydrogen gas, leading to bulging or deformation of the capacitor's case, and eventual venting of the electrolyte. In rare cases, the faulty capacitors have even been reported to pop or explode forcefully.
Electrolytic Capacitors infected with Capacitor Plague:
The difference between solid state capacitors and electrolytic capacitors is that solid capacitors contain a solid organic polymer, while electrolytic capacitors use a common liquid electrolyte. As there is no liquid component to solid capacitors, they don't experience leaking or exploding. In addition, their ability to tolerate extreme conditions and their overall robustness, make them much more suited to extreme stress operation.
Solid State Capacitor:
Thanks:
Thanks guys for bearing with me. I know the images are edited badly but i have done the best i could
.Please Leave a comment on how i have written/compiled this walkthrough. Thanks Again 
