Motherboard Interview Questions & Answers

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The central processing unit (CPU) is the brain
of your computer. It handles all the instructions
you give your computer, and the faster it does
this, the better. Learn about how a CPU
processes instructions and how computer
engineers are continuously coming up with ways to make it go faster.

The IBM POST beep codes are as follows:

★ 1 short beep: This indicates that the POST was normal without any exceptions.
★ 2 short beeps: This indicates there was an error and the message is displayed on the screen.
★ No beep: Indicates no power or disconnection.
★ Continuous beep: This is indicative of a power supply, motherboard or a keyboard problem.
★ One long one short beep: this is indicative of a problem with the mother / system board.
★ One long two short beeps indicates that there is a problem with the display adapter

The modern motherboards at a minimum contain at least:

★ Sockets: The sockets are used to install the processor.
★ The memory slots where the user can install the main memory for the system.
★ Chipset: The chipset is used as a the interface for communication between the processor, main memory and the bus.
★ Flash ROM: These store permanents information such as the BIOS, firmware etc.
★ Power connector: The power connector is connected with the SMPS to deliver power to the components on the motherboard.
★ Expansion slots: The expansion slots are used for various devices to be connected to the system.

The DOS control can be explained in the following steps:
★ The first step the boot loader loads the boot record to the memory, which is given the control ( boot program ) inside the boot record.
★ This program now check for the IO.SYS and MSDOS.SYS as the first entries.
★ Now the program loads the IO.SYS and is given control.
★ The IO.SYS simply loads the MSDOS.SYS file and starts looking for the CONFIG.SYS file .
★ Finally the MSDOS.SYS file is given control, this file now initializes interrupt vectors and loads the COMMAND.COM file.
★ Lastly the autoexec.bat file is loaded, executed.

Characteristics of micro programmed control units:
★ These control units are implemented as micro programs of routines.
★ The control unit implemented in micro program is implemented in the form of a CPU inside another CPU.
★ These types of circuits are simple but comparatively slower.

The characteristics of hardwired control units are as follows:
★ Hardwired control units are based on combinational circuits.
★ In these type of systems the inputs and transforms are set into control signals.
★ Theses units are faster and are known to have a more complex structure.

Some of the purposes for which the LSI are used are as follows:

★ PIC or the programmable interrupt controller.
★ PIT or the programmable interrupt timer.
★ PPI or programmable peripheral interface.
★ CRTC is used for the controlling of the CRT.
★ The floppy disk, hard disk and DMA controller are used for special purposes.
★ The real time calendar or clock is used to organize and sort out things.

★ Multiple programs can be present in the memory at a given time.
★ The resources are dynamically allocated.
★ The size of the memory is larger comparatively.

★ Uni programming allows only one program to be present in memory at a time.
★ The resources are provided to the single program that is present in the memory at that time.
★ Since only one program is loaded the size is small as well.

★ The physical address as the name suggests is the actual location which can be found in the memory.
★ They are used by the CPU in order to specify the range of addresses.

★ The logical address is used by the CPU and is actually a specification.
★ It is used to represent the size of the CPU address register size.

USB: Usb ports are also present on the motherboard that allows the user to connect various external devices.

Sound card: Most motherboards these days are preinstalled with a 8 channel audio chip.

Ethernet network controller: The motherboards also come preinstalled with a LAN port for networking purposes.

Integrated graphics: Most budget motherboards come with a GPU installed on it that supports VGA / HDMI and DVI out.

Controllers: Disk controllers are present on the motherboards that can be used to manage floppy drives and SATA / PATA hard disk drives.

★ Controllers
★ Integrated graphics
★ Sound card
★ Ethernet network controller
★ USB

Some of the prime functions of a computer motherboard are as follows:
★ The motherboard acts as the central backbone of a computer on which other modular parts are installed such as the CPU, RAM and hard disks.
★ The motherboard also acts as the platform on which various expansion slots are available to install other devices / interfaces.
★ The motherboard is also responsible to distribute power to the various components of the computer.
★ They are also used in the coordination of the various devices in the computer and maintain an interface among them.

★ The CPU registers are verified.
★ The BIOS code integrity is checked.
★ The basic components such as the DMA, timer etc are checked.
★ The system memory is verified and checked.
★ All the system buses are discovered, cataloged and executed, activated.
★ BIOS is initialized after it.
★ Ready the environment that is required by the OS to function.

POST or the power on self test is a routine that is executed immediately once the system is powered on. It is only after POST that a system allows the bootstrap loader to be initialized. The POST is performed to ensure that the system peripherals are connected and functioning and there are no compatibility issues.

PC design has greatly improved in the last decade primarily in these areas:

★ Microprocessor:
Today a normal desktop PC can have processors which have exceeded 3gHz limits and can have more than one physical core.
★ Peripherals:
The list of devices that can be connected to the computer via various ports have increased.
★ Hardware components:
The level of components that are being used have also increased in complexity.
★ OS:
The operating systems being used today have also greatly improved supporting more higher hardware specifications.
★ Layouts:
The layouts and modules being used for computers have also greatly improved.

In primary storage device the storage capacity is limited. It has a volatile memory. In secondary storage device the storage capacity is larger. It is a nonvolatile memory. Primary devices are: RAM / ROM. Secondary devices are: Floppy disc / Hard disk.

Primary storage device is Ram where the instructions are stored for temporary and secondry storage is hard disk floppy cds etc.

If you open your computers case, the motherboard is the flat, rectangular piece of circuit board to which everything seems to connect to for one reason or another.

Its the circuit board which contain processor,north bridge&south bridge and slots.

Microprocessor is a program-controlled device, which fetches the instructions from memory, decodes and executes the instructions. Most Micro Processor are single- chip devices.

A single chip CPU is called as Microprocessor.The CPU is made of two units namely the Arithmetic and Logic Unit and the Control Unit.It performs functions like executing the instructions given by the user program, controlling the I/O operations and the functions of peripheral devices