Explore topic-wise InterviewSolutions in .

A set of wire is connected between the control unit and other units like memory, Input/ Output device.

The control bus is used for transmission of control signals to coordinate the operations of various units of the computer.

It is an internal bus that connects major components like processor, memory and I/O. The data transfer takes place in high speed.

The expansion of UPS is Uninterruptable Power Supply.

The registers are high-speed temporary storage units within the CPU. Its main purpose is to store data and instructions during processing by the CPU.

The term SMPS is expanded as Switch Mode Power Supply.

The registers are high-speed temporary storage (memory) of CPU. It is CPU’s working memory and uses to store data and instructions during program execution.

The approximate power consumed by a PC (Computer) is around 300 Watts.

The SMPS gives controlled regulated converted DC power to all the units of computer.

The ALU performs all arithmetic and logic operations on the data.

The PCI is expanded as Peripheral Component Interconnect.

The expansion of DVI is Digital Video Interface.

The CU is said to be the nervous system of computer and it controls the overall operations of the computer.

The UPS give power supply during the outage of main power supply to the computer.

The system or expansion bus consists of data bus, address bus and control bus.

The DVI port connects flat panel LCD monitor to high-end video graphics card of the system.

The IDE expansion is Integrated Digital Electronics.

The Hard disk controller is the interface that enables to read and write information to the hard drive.

The serial port can transfer data serially on bit at a time.

BIOS is a small chip that holds a set of instruction to load the hardware settings required to activate basic components of computer like keyboard, monitor, etc.,

The term ATX motherboard expansion is Advanced Technology extended motherboard.

The RAM and ROM are examples for primary memory.

1. The Databus:
A group of wire is connected between the control unit and other sections (Input/Output device). These are bi-directional (two directions).

2. Address bus:
A collection of wires connecting the CPU with main memory that is used to identify particular locations (addresses) in main memory. The address bus is unidirectional (one direction).

The expansion of BIOS is Basic Input Output System.

Magnetic disks, Magnetic tape, optical disks are the examples for secondary memory.

COM/Serial ports: [Component Object Model]
It is used for connecting communication devices like modems or mice. Serial ports provide the serial transmission of data of one bit at a time. There are two types namely, COM ports - pin ports and 25- pin ports.

Plug-n-play device means devices can be inserted or removed into the computer system while the system is switched ON and working.

• USB provide higher data transfer speed for Plug-n-play devices like keyboard, mice, scanners, printers, digital cameras, thumb drives, etc.,
• USB allows multiple devices as many as up to 127 to run simultaneously on a computer.

The data speed of the USB port is 12 megabits per second.

Pen drives/Printers/Mouse are one of the USB devices.

Parallel ports are used to connect external input/output devices like scanners or printers. They provide parallel transmission of data, of 1 byte (8 bits) at a time. Parallel ports use 25 pin RS-232C.

The L2 cache is located near the motherboard(RAM).

The different internal memory are registers, cache memory, and primary memory.

Universal Serial Bus

The cache that comes with the (CPU) processor called Level one (L1) cache.

This is a single computer bus that controls the transfers between the CPU, the main memory, and the input/output devices.

The extended Technology motherboards are old model motherboards. Slot type processors, Low insertion Force (LIF) sockets, DIMM RAM slots and ISA slots with 12 pin power connectors can be seen. Example, P1, P2, and Pentium MMX processors.

The instruction execution cycle performs the following steps:

a. Instruction Cycle:

1. Instruction Fetch
2. Instruction Decode

1. Instruction Fetch:
The first step is to fetch the instruction to be executed. This is called Instruction Fetch operation. Execution of the program starts from the Program Counter Register (PC) which has the first instruction of the program. The contents of the PC are then transferred to the Memory Address Register (MAR) and a READ signal is sent to the memory and is read out and loaded into the Memory Data Register (MDR). Later, the contents of the MDR are transferred to the Instruction Register (IR).

2. Instruction Decode:
In the instruction Decode operation, the Instruction Register (IR) determines the type of instruction and selects signals accordingly. It separates the operation part of instruction and is sent to the control unit and the address part is sent to MAR of the instruction.

b. In Execution cycle:
The decoded instruction is executed finally. Instruction Decoder generates microinstructions and the timing signals that control the various processing elements involved in executing the instruction.

These are devices that work with a computer system as soon as they are connected. The user does not have to manually install drivers for the device or even tell the computer that a new device has been added. Instead, the computer automatically recognizes the device, loads new drivers for the hardware if needed, and begins to work with the newly connected device.

The Southbridge is an integrated circuit on the motherboard that is responsible for the. hard drive controller, I/O controller and integrated hardware such as sound card, video card if present on the motherboard, USB, PCI, ISA, IDE, BIOS, and Ethernet.

It refers to the speed of the processor. The clock speed is measured in terms of MegaHertz (millions of pulse per second) or Gigahertz (billions of pulses per second). The clock speed ranges from 1000 MHz to 3000 GHz. It means in 1000 MHz clock speed processor, can perform approximately 1000 million instructions per second. The faster the clock speed, the faster the processing speed. 

Ex: 2.7 GHz processor, 3.0 GHz processor, etc,

The port has either holes or a slot that matches the plug or card being connected to the port. A PS/2 port found on the back of computers that allows a keyboard and mouse with a PS/2 connector to be connected to the computer. The bus connects major components like processor, memory and I/O internally and also connects the different external devices and ports thus expanding the computer's capabilities.

It is the combination of XT and AT and has slot type processor sockets and also PGA processors sockets, SDRAM slots and DDR RAM slots, PCI slots and ISA slots, 12 pin and 20 pin power connectors and ports. 

Example: Motherboard for Pentium 3 and Pentium 4 processors.

The northbridge is an integrated circuit (IC ) is responsible for communications between the CPU interface, AGP, and memory. The Northbridge is directly connected to these components and acts like a “bridge” for the Southbridge chip to communicate with the CPU, RAM, and graphics controller. Today, the northbridge is a single-chip that is North of the PCI bus, however, early computers may have had up to three separate chips that made up the northbridge.

Universal Serial Bus (USB) connectors:

Universal Serial Bus, USB is a standard that was introduced in 1995 by Intel, Compaq, Microsoft, and other computer companies. USB 1.x is an external bus standard that supports data transfer rates of 12 Mbps and is capable of supporting up to 127 peripheral devices.

USB 2.0, also known as hi-speed USB, is capable of supporting a transfer rate of up to 480 Mbps and is backward compatible, meaning it is capable of supporting USB 1.0 and 1.1 devices and cables. USB 3.0 also known as SuperSpeed USB is the latest version of the USB protocol.

Most new computers provide USB 3.0 ports built-in, offering data transfer speeds of up to five gigabits per second. USB provides high-speed data transfer for Plug-n-play devices like keyboard, mice, scanners, printers, digital cameras, thumb drives, etc.,

The different I/O ports are serial port, parallel port, USB port, and AGP port, etc.,

1. COM/Serial ports: [Component Object Model ]
It is used for connecting communication devices like modems or mice. Serial ports provide the serial transmission of data of one bit at a time. There are two types namely com ports – 9 pin ports and 25- pin ports.

2. Parallel ports:
Used to connect external input/output devices like scanners or printers. They facilitate the parallel transmission of data, of 1 byte (8 bits) at a time. Parallel ports use 25 pin RS- 232C.

3. Universal Serial Bus (USB) connectors:

• USB provides high-speed data transfer for Plug-n-play devices like keyboard, mice, scanners, printers, digital cameras, thumb drives, etc.,
• The data transfer speed in USB 1.0 is 12 Mb per second, USB 2.0 is 480 Mb per second and USB 3.0 is 5 Gb per second.
• USB allows multiple devices as many as up to 127 to run simultaneously on a computer.

The AGP is an advanced port designed for Video cards and 3D accelerators designed by Intel. AGP is to provide enhanced graphic accelerator cards, thus enhancing the picture quality of the screen.

4. PS/2 connectors:
Stands for “Personal System/2” (PS/2) are used to connect input devices like PS/2 keyboards or mice.

5. IDE drive connector:[lntegrated Drive Electronics]
IDE devices like Harddisk drives, CD-ROM drives are connected via a 40-pin ribbon cable.

The different components of the motherboard are CPU processor, BIOS, CMOS, Slots, I/O ports, Bus, and Slots.

Standard Configuration of a PC

The port has either holes or a slot that matches the plug or card being connected into the port. A PS/2 port found on the back of computers that allows a keyboard and mouse with a PS/2 connector to be connected to the computer.
The bus connects major components like processor, memory and I/O internally and also connects the different external devices and ports thus expanding the computer's capabilities.

1. COM/Serial ports: [Component Object Model ]
It is used for connecting communication devices like modems or mice. Serial ports provide the serial transmission of data of one bit at a time. There are two types namely com ports – 9 pin ports and 25- pin ports.

2. Parallel ports:

Used to connect external input/output devices like scanners or printers. They facilitate the parallel transmission of data, of 1 byte (8 bits) at a time. Parallel ports use 25 pin RS- 232C.

3. Universal Serial Bus (USB) connectors:

• USB provide high-speed data transfer for Plug-n-play devices like keyboard, mice, scanners, printers, digital cameras, thumb drives, etc.,
• The data transfer speed in USB 1.0 is 12 Mb per second, USB 2.0 is 480 Mb per second and USB 3.0 is 5 Gb per second.
• USB allows multiple devices as many as up to 127 to run simultaneously on a computer.

The AGP is an advanced port designed for Video cards and 3D accelerators designed by Intel. AGP is to provide enhanced graphic accelerator cards, thus enhancing the picture quality of the screen.

4. PS/2 connectors:
Stands for “Personal System/2” (PS/2) are used to connect input devices like PS/2 keyboards or mice.

5. IDE drive connector:[lntegrated Drive Electronics]
IDE devices like Harddisk drives, CD-ROM drives are connected via a 40-pin ribbon cable.

6. Floppy drive connector:
Used for connecting the floppy drive to the PC. It is a 34-pin ribbon cable.

The power supply to computer can be categorised into two types. Namely, Switch Mode Power Supply (SMPS) and Uninterruptible Power Supply (UPS).
SMPS:
The switched-mode power supply acting as a DC to DC converter first rectifies an AC input voltage (240Volts), converts it to DC and, chops this DC in a “chopper” and converts it to a higher or lower level of DC (5 to 12 V DC Volts )or perhaps both a higher AND lower level of DC. Typical modern applications include computer power supply and the power supplies in TV and Video sets. The wattage of SMPS is around 150 to 500 watts.

SMPSs are three types.

1. AT SMPS
2. ATX SMPS
3. BTXSMPS

1. AT SMPS:
AT stands for Advanced Technology. These are all. old SMPSs. They had 12pin power connector, this is called an AT power connector. They were used in Pentium-1, Pentium- MMX, Pentium-ll and Pentium-Ill CPUs.

2. ATX SMPS:
ATX stands for Advanced Technology extended. They had a 20pin Power connector, this is called an ATX power connector. They were used in Pentium-Ill, Pentium-IV and AMD CPUs.

3. BTXSMPS:
BTX stands for Balanced Technology extended. They have a 24pin Power connector, this is also called an ATX power connector. It has 15pin SATA power connectors. They are used in Dual-core, core2duo, Quad-core, i3, i5, i7 and latest AMD CPUs.

4. Uninterruptible Power Supply (UPS):

• UPS unit give continuous power supply in the event of the main source power break.
• It also regulates the high and IQW voltage in power supply.
• On-line and Off-line UPS are the two kinds of UPS.
• They give different backup power ranging from 15 minutes to several hours.

UPS is Uninterruptible Power Supply, this is also known as power backup with battery. 

With UPS even the main power source down, this unit will always give power to computer. UPS have a limit time to give backup power, this depends on how big the UPS capacity.

5. Working of UPS:
With simple explanation inside UPS have battery with recharge module, it also have module to determine whether the main power source on or off, so when the main power source on, the recharge module will charge the battery till full. When the main power source suddenly off, then the module will switch on the battery changed into a backup power source.

Two types of UPS are Offline and Online UPS.

1. Offline UPS (standby UPS):
This UPS type have a module to switch between using battery or using bypass main power source. When the main power source is off, then the module will switch from the main power source to the battery source in less than 4ms delay time and supply power to the computer.

2. Online UPS
This UPS type is better than Offline because no matter the main power source is on or off, this Online UPS output always come from battery source. That’s why this type of UPS does not have delay time when the main power source is off or on. The price for Online UPS is more expensive than Offline UPS.