If you have any (whys, Hows and what four`s) please share

BIOS - (basic input-output system)

The BIOS is a very important part of a Computer System and not that hard to understand or at times use

The BIOS software has a number of different roles, but its most important role is to load the operating system. When you turn on your computer and the microprocessor tries to execute its first instruction, it has to get that instruction from somewhere. It cannot get it from the operating system because the operating system is located on a hard disk, and the microprocessor cannot get to it without some instructions that tell it how. The BIOS provides those instructions. Some of the other common tasks that the BIOS performs include, a power-on self-test (POST) for all of the different hardware components in the system to make sure everything is working properly, activating other BIOS chips on different cards installed in the computer - For example, SCSI (Small Computer System Interface) and graphics cards often have their own BIOS chips, providing a set of low-level routines that the operating system uses to interface to different hardware devices - It is these routines that give the BIOS its name. They manage things like the keyboard the screen and the serial and parallel ports especially when the computer is booting, managing a collection of settings for the hard disks, clock, etc.

The BIOS is special software that interfaces the major hardware components of your computer with the operating system. It is usually stored on a Flash memory chip on the motherboard, but sometimes the chip is another type of Rom.
When you turn on your computer, the BIOS does several things. This is its usual sequence -

1. Check the CMOS Setup for custom settings

2. Load the interrupt handlers and device drivers

3. Initialize registers and power management

4. Perform the power-on self-test (POST)

5. Display system settings, white text on a black screen "sometimes color"

6. Determine which devices are bootable and which to go boot in sequence

7. Initiate the bootstrap sequence

The first thing the BIOS does is check the information stored in a tiny (64 bytes) amount of RAM located on a complementary _meta_l oxide semiconductor (CMOS) chip. The CMOS Setup provides detailed information particular to your system and can be altered as your system changes. The BIOS uses this information to modify or supplement its default programming as needed.
Interrupt handlers are small pieces of software that act as translators between the hardware components and the operating system. For example, when you press a key on your keyboard, the signal is sent to the keyboard interrupt handler, which tells the CPU what it is and passes it on to the operating system. The device drivers are other pieces of software that identify the _base_ hardware components such as keyboard, mouse, hard drive and floppy drive. Since the BIOS is constantly intercepting signals to and from the hardware, it is usually copied, or shadowed, into RAM to run faster.

Ann

Motherboards

A motherboard is also known as a main board, system board and logic board. A common abbreviation is "mobo" they can be found in all computers, it is the central circuit board of your computer. All other components and peripherals plug into it, and the job of the motherboard is to relay information between them all.

A motherboard houses the BIOS (Basic Input/Output System), which is the simple software run by a computer when initially turned on. Other components attach directly to it, such as the memory, CPU (Central Processing Unit), graphics card, sound card, hard-drive, disk drives, along with various external ports and peripherals.

There are a lot of motherboards on the market to choose from. The big question is, how do you go about choosing which one is right for you? different motherboards support different components, and so it is vital you make a number of decisions concerning general system specifications before you can pick the right motherboard, what type of Computer do you want to build, an Intel _base_d or AMD _base_d "the two most common".

If you purchase your case before the rest of the components, the first factor to think about concerning motherboards is the size, or form factor, a form factor is a standardized motherboard size, if you think about fitting a motherboard in a case, there are a number of mounting holes, slot locations and PSU connectors - 20 pin and mostly now 24 pin. The most popular motherboard form factor today is ATX, which evolved from it's predecessor, the Baby AT, a smaller version of the AT (Advanced Technology) form factor. Nowadays a standard computer will have an ATX form factor motherboard: only special cases require different form factors, (some form factors below, and please do consult the information within the _link_ also below as this is from Wikipedia and is updated regularly). Picture of a Motherboard and _link_ below

Some Form Factors


Motherboard


Motherboard Form Factor _link_ > Wikipedia

Ann

SLI

I ran SLI in early 2006 with two GeForce 6600 GTs on a MSI K8N Platinum SLI motherboard, GPU drivers (v71.81) and nVidia nForce drivers (v6.39) + DDR3 SLI Bridge, worked very well

(SLI) Scalable _link_ Interface is a brand name for a multi-GPU solution developed by nVidia (thats two nVidia Graphics Cards running in sync on one Motherboard) this configuration when gaming works with (profiles) nVidia has created an extensive set of over 500 custom application profiles which enable SLI technology automatically and optimize scaling performance, you can also submit a request to have this profile for a game not in the list added to the next driver release. Picture and more to read in the _link_ below-

Click on image to enlarge



_link_ > nVidia SLI Zone

Crossfire

ATI - Now ATI / AMD Crossfire But i will just call them ATI

This Graphics Card system requires a Crossfire-compliant Motherboard with a pair of PCI Express (PCIe) graphics cards, which can be enabled via either hardware or software. Radeon x800s, x850s, x1800s and x1900s come in a "Crossfire Edition"' that has "master" capability built into the hardware. So you need a Master card, and pair it with a normal card from the same series. Radeon x1300s and x1600s have no "Crossfire Edition" but are enabled via software. ATI currently has not created the infrastructure to allow FireGL cards to be set up in a Crossfire configuration. Another point to note is that the "slave" graphics card needs to be from the same family as the "master", regardless of whether the master is designated by the hardware or by software, ATI`s Catalyst.
With the release of the Radeon X1950 Pro GPU, ATI revised Crossfire's connection infrastructure to eliminate the need for past Y-Dongle/Master card and slave card configurations for Crossfire to operate. ATI's Crossfire connector is now a ribbon like connector attached to the top of each Graphics Card, similar to nVidia's SLI bridge, but different in physical and logical natures.
nVidia and ATI are locked in a Graphics Card War, nVidia concider ATI to be a threat and vice versa, each camp produce some good Cards more on Crossfire in the _link_s below

Note A single new high end Graphics Card is capable of playing about any game on the market

More on Crossfire > Here

ATI Radeon HD 2900XT Spec > Here

2900XT`s in Crossfire, click image to enlarge