Things U Need 2 Know....

Pci Slots:Conventional PCI (part of the PCI Local Bus standard and often shortened to PCI) is a computer bus for attaching hardware devices in a computer. These devices can take either the form of an integrated circuit fitted onto the motherboard itself, called a planar device in the PCI specification, or an expansion card that fits into a slot. The name PCI is an initialism formed from Peripheral Component Interconnect. The PCI Local Bus is common in modern PCs, where it has displaced ISA and VESA Local Bus as the standard expansion bus, and it also appears in many other computer types. Despite the availability of faster interfaces such as PCI-X and PCI Express, conventional PCI remains a very common interface.

Typical PCI cards used in PCs include: network cards, sound cards, modems, extra ports such as USB or serial, TV tuner cards and disk controllers. Historically video cards were typically PCI devices, but growing bandwidth requirements soon outgrew the capabilities of PCI. PCI video cards remain available for supporting extra monitors and upgrading PCs that do not have any AGP or PCI Express slots.
When purchasing PCI expansion cards you need to be careful about compatibility with the PCI expansion slots on the motherboard. There are two things which vary in PCI expansion slots: the voltage, and the number of bits. PCI Slots can support either 3.3 volts or 5 volts. PCI has a system of keys which only allows expansion cards to fit into the motherboard connector if it provides the correct voltage. As shown in the picture above, a 5 volt PCI motherboard connector has a key near the right end. A 5 volt PCI expansion card has a slot which lines up with the key. That allows you to plug a 5 volt PCI card into a 5 volt PCI connector. You can see a "real" PCI connector in the motherboard picture above. 3.3 volts is similar but its key is near the left end. This system allows you to plug 5 volt cards into 5 volt PCI connectors but not into 3.3 volt PCI connectors. Likewise, you can only plug 3.3 volt cards into 3.3 volt PCI connectors and not into 5 volt connectors. If the expansion card can run on both 3.3 and 5 volts then it has both slots and fits into both 3.3 and 5 volt PCI motherboard connectors. PCI expansion slots also support two different widths: 32 bits, and 64 bits. The 64 bit motherboard connector is longer than a 32 bit connector. Most PC motherboards come with 32 bit slots but some come with 64 bit slots. A 32 bit PCI expansion card will work fine in a 64 bit slot. PCI video cards are 32 bit cards. 

BIOS(Basic input output sysytem):The BIOS is boot firmware, designed to be the first code run by a PC when powered on. The initial function of the BIOS is to identify, test, and initialize system devices such as the video display card, hard disk, floppy disk and other hardware. The BIOS prepares the machine for a known state, so that software stored on compatible media can be loaded, executed, and given control of the PC. This process is known as booting, or booting up, which is short for bootstrapping.
BIOS programs are stored on a chip(ROM) and are built to work with various devices that make up the complementary chipset of the system.

CMOS(Complementary metal–oxide–semiconductor):As described above in your computer is a chip called the BIOS chip. This chip contains all of the basic instructions that tell your motherboard how to operate. However, every motherboard has several settings that can be changed by the user, including the date and time, the types of drives installed in the computer, the system bus speed and more. These settings cannot be saved to the BIOS, because the BIOS exists on a type of memory that cannot be written to called ROM. To retain your settings, the motherboard also has a second type of memory called the CMOS. CMOS memory can be written to, but it also requires a very small electrical current in order to retain this information. Therefore, the CMOS is powered by a battery. Because of the CMOS battery, all of your settings are saved even when the computer is turned off or disconnected from a power source.
note:"CMOS is a type of battery often used to power the circuit which allows the information in BIOS to be stored. If the CMOS battery is drained or removed all the system configuration data in BIOS will be reset to factory defaults every time the computer is shut off."



AGPslot:The Accelerated Graphics Port (also called Advanced Graphics Port, often shortened to AGP) is a high-speed point-to-point channel for attaching a video card to a computer's motherboard, primarily to assist in the acceleration of 3D computer graphics.
 As computers became increasingly graphically oriented, successive generations of graphics adapters began to push the limits of PCI, a bus with shared bandwidth. This led to the development of AGP, a "bus" dedicated to graphics adapters.
The primary advantage of AGP over PCI is that it provides a dedicated pathway between the slot and the processor rather than sharing the PCI bus. In addition to a lack of contention for the bus, the point-to-point connection allows for higher clock speeds.





South Bridge:The south bridge incorporates a number of different controller functions. It looks after the transfer of data to and from the hard disk and all the other I/O devices, and passes this data into the link channel which connects to the north bridge.