Motherboard Cheking

To check motherboard we have to take following steps:

1. Check motherboard for cracks on account of overheating of equipment.
2. Physically observe any scratches or discontinuity in PCB(Printed Circuit Board) path.
3. Check for burnt ICs or component.
4. Check the VGA connector for dry soldering or loose connection or replace the connector.
5. Check North Bridge and South Bridge ICs physically for loose connection or dry soldering.
6. Check north and south bridge IC whether they are getting heated by putting your index finger on them.
7. Check the processor whether it is gradually heating up or not by putting your index finger on top of the processor.
8. If the processor is cool then check the voltage regulator ICs whether short or open or measuring  voltage across the leads using multimeter in diode mode.
9. Update BIOS from motherboard driver CD or you can download from the Internet.
10. Replace BIOS and check.
11. Use the debugging card to know the source of the problem.

Troubleshooting of Motherboards

If your system Crashes repeatedly,it is possibly due to motherboard failure. However , actual motherboard failure is very rare. It is possible that some other problems like a loose connection, power failure or overheating may cause system failure.

We have to take the following steps :

• Turn off the system and remove the power cord from the power supply.
• Check connections on the Motherboard .
• Restore the BIOS settings to default setting .
• Ensure that the motherboard is not touching the system case.

Precautions:

• Wear an anti static wristband.
• Cleaner 

COMS battery checking

Actually CMOS is not a battery ,it is a technology which is used to construct Integrated Circuit. CMOS stands for Complementary Metal Oxide Semiconductor. This technology is basically used in microprocessor, micro-controller,RAM ,different logic circuit.
To check the CMOS battery we have to take following steps:

1. Remove the CMOS battery from the motherboard.
2. Set the multimeter in DC voltage mode
3. Put the red probe on +ve side (mentioned on the CMOS battery) and black probe on opposite side of the CMOS battery.
4. If the output voltage shown is grater than 2.5 volts on  multimeter then it is OK otherwise replace the battery.

Thank You

Starting a PC for the First Time

When we start the PC,the Basic Input Output System(BIOS) runs a test to check if all the peripheral devices ,memory and hardware of the PC will are working properly.This test is called the Power on Self Test (POST). The PC will boot only if the results of the test are positive.POST is performed before the PC actually boots the operating system.

If any the hardware components of the PC are not in proper condition, the PC will generate beeps.In some cases,if the problem is serious,the PC will not boot at all. The POST happens before most of the components of the PC start.

The following are the functions performed by POST:

• Checking the power supply
• Checking the motherboard
• Comparing the system configuration with the PC configuration program to find any changes made
• Checking the memory devices and drives
• Checking the System memory
• Starts the display and audio devices

The error that causes the system to stop booting are of two types-Non-Fatal and fatal. In case of non-fatal errors like problems in the extended memory,an error message usually appears on the screen.They allow the computer to continue the boot process. In-case of fatal errors like problems in the processor,the boot process stops immediately and the user gets a series of audible beeps. In-case there are no errors in the system configuration or devices,a single beep follows the POST . Then the booting process of the PC starts and the operating system is loaded.

Thank You

All the User account (including Administrator) are disable

First you have to enable administrator account. To do that the several steps have to be taken-

1. Restart your System and hit several time F8 key.
2. Chose "Safe mode with command prompt."
3. In command prompt  type 

          "net user administrator /active:yes"

    4. Protect your administrator with password.

Create System Image and System Repair Disc

• Run this task by Administrative Rights

Hardware/Software Requirements:

• External Hard disk/ Blank DVD Disk

To Create System Image and System Repair Disc

1. Click Start→Control Panel→System and Security→Backup and Restore
2. Click on Create a system image 

          select your option among the three options

          a. On a hard disk

          b. On one or more DVDs

          c. On a network location   

     3. Select the disk where you want to save the backup and click Next button.

     4. Click Next Button.

     5. Click on Start backup button. Create a system Image screen appear.

     6. Create a system repair disc screen appear.

     7. Click on Yes button and Insert a blank writable DVD in DVD-ROM Drive.

     8. Click Create Disc.

     9. The creating a System Repair  Disk dialog box appears.

    10. Using the system repair disc screen appears.

    11. Click Close.

OSI Layer and their function

   LAYERS                     FUNCTIONS                        DATA FORMAT             DEVICE USED

7 Application           Creating a data at user interface             File                             Computer

6 Presentation          Copressing ,encription                           File                            Computer

5 Session               i. Establish connection between
                                transmiter and receiver .                        N.A                          Computer
                             ii. Maintaning, controling,teminating
                                the communication

4 Transport            Identifying the relevant process or we       Segment                  Computer
                              can say: "Process-to-process "delivery.

3 Network             Identify relevant host or we can say         Data gram                 Router
                               "host-to-host" delivery .

2 Data link            Identifying relevant hardware.                   Frame                         Switch

1 Physical             Use for  establishing electrical link            Bits( 0 & 1 )     Hub,Cable,wires
                            between the each pair of devices.
                   

Boot MGR missing

When a message like 'boot mgr missing press Alt+Ctrl+Del to restart'

• First goto BIOS and set CD or DVD drive as first boot priority .
• Now insert microsoft product DVD 'on system repair disk and restart the computer'.
• Click on the repair option .Its starts finding the OS location on the hard disk and after few second the exact drive letter with size will appear.
• You can see that your operating system is there in a drive say(Ex. C:).
• Now you also see in the same box -two options

          a. Repair your computer.

          b. System image.

Select the 1st option .You will now find several options to repair your computer among them choose  'start to repair ' your system automatically start repairing your OS and finally it will produce report.Go through the report and see each testing steps whether it is completed successfully or not.If all steps completed successfully then your system is repaired.
If not then perform next step.
Among those several options as explained command prompt.

           :\>c:

           c:\>dir

           c:\>bootrec fixmbr

           c:\>bootrec fixboot

           c:\>bootrec rebuild bcd

           c:\>exit

•  Restart your computer