Troubleshooting Tips Guide

Common Computer Hardware

(1) Trial-and-error

Personal computers are highly modular by design. The most powerful trouble-shooting technique is to isolate the problem to a specific component by trial-and-error. Swap compatible components and see if the system still works. Try different peripherals on different machines and see if the same problem occurs. Make one change at a time.

(2) The cables

More than 70% of all computer problems are related to cabling and connections. Ensure all cables are connected firmly. IDE and floppy ribbon cables and power cables can often go loose. Ensure microprocessor, memory modules, and adapters such as video card and sound card are inserted correctly and didn't "pop-up" during transportation.

(3) Don't be frustrated

Don't be afraid of computer problems. It is often the best opportunity to learn. Trouble-shooting is part of the fun of owning a computer. Imagine the satisfaction you could get by solving a problem yourself.

Of course the fun could ran out quickly once you are frustrated and have spent too much time on the same problem. If you feel frustrated, it's time to leave it for a while and go back with some new ideas or call someone who can help. Rule of thumb: You shouldn't spend more than three hours on the same problem at one time.

(4) Take notes!

Take notes of what you have done and all the error messages. You may need to use them later. For instance, when you see an unusual blue screen with an error message, copy the entire message onto a piece of paper. In many situations, that message may point to the right direction in getting the problem solved quickly.

(5) Take a look

It's OK to open a computer case and take a look inside. There is only 5V and 12V DC voltage supplied to the components outside the power supply. Those who have never seen the inside of a computer are often amazed by how simple it looks. Of course, still always power down and unplug the power cord first.

Monitors:

  1. The picture does not appear
     
    • Check to make sure the signal cable is firmly connected in the socket.
    • Check to see if the computer system's power is ON.
    • Check that the Brightness Control is at the appropriate position, not at the minimum.
  2. The Screen is not synchronized
     
    • Check to make sure the signal cable is firmly connected in the socket.
    • Check that the output level matches the input level of your computer.
    • Make sure the signal timing of the computer system is within the specification of the monitor.
  3. The position of the screen is not in the center
     
    • Adjust the H-Size, H-Phase or V-Size, V-Center controls.
    • Check if the signal timing of the computer system is within the specification of the monitor.
  4. The screen is too bright or too dark
     
    • Check if the Brightness or contrast control is at the appropriate position, not at the maximum or minimum.
    • Check if the specified voltage is applied
    • Check if the signal timing of the computer system is within the specification of the monitor.
    • Especially, check the horizontal frequency.
  5. The screen is shaking
     
    • Move all objects that emit a magnetic field, such as a motor or transformer, away from the monitor.
    • Check if the specified voltage is applied.
    • Check if the signal timing of the computer system is within the specification of the monitor.

Modem

My modem is a 56K, but I can connect to the Internet only at slower speed.
The current copper wired telephone lines are limited only to about 53K. If you are connected only to 33.6 or 28.8K, check the following first:

  • Is your modem compatible with the modem used at your ISP?
  • Is your modem set up to run at full speed?
  • What's the maximum speed your ISP allows?
  • How far away are you from your ISP?
  • Some modems need special initiation strings to get full speed.
  • Some conditions are out of your control, such as weather and conditions of the telephone lines in your community.
  • Problems may occur when you are dialing through a phone system such as one in a hotel.

Modem answers incoming calls and then returns to the on-hook condition, disconnecting the caller:
This occurs most often when connecting to a UNIX system. In most case, the host does not prefer to see any result or command echo codes. If this is the case, the codes can be disabled by adding E0 Q1 to the modem configuration string.

The modem dials and appears to complete the connection, but the communications software does not enter the correct mode. (The screen remains blank)
This is normally caused by an I/O address or IRQ conflict. Verify that the COM port is not in use by any other serial device and if necessary use another COM port or I/O address settting. Refer to your computer manual on how to determine what serial ports are installed.

The modem dials and appears to complete the connection, but the communications software does not enter the correct mode. (The screen remains blank)
 

  • There may be an I/O conflict (see the solution for the previous problem).
  • The Result Codes may have been disabled by the software configuration set up. Check if Q1 is in the configuration or initialization string. If so, change it to Q0.
  • Your software may require numeric result codes rather than verbal result codes. Use either V0 for numeric result codes or V1 for verbal result codes in your initiazation or configuration string.
  • Some software require full extended result codes (i.e., CONNECT 33600 instead of CONNECT). This can be controlled by the Xn command. X0 sends a summarized code (CONNECT) and X4 sends a full extended code (CONNECT 33600)

The modem does not auto answer
The auto answer mode is determined by the S0 register. If S0 has been set to 0, the modem will not answer. Asign another value to S0 by entering the following command: S0=n, where n = the number of rings to occur before the call is answered (ATS0=2, the modem answers after two rings)

The modem always answers the phone.
Set the S0 register to 0. ATS0=0.

The communications software displays, "No Dial tone."
Make sure that your phone cable is working properly and that it is firmly seated to the phone socket at your phone jack and in the real panel of the modem.

A high pitched squeal is emitted from the external speakers
This phenomenon is "feedback" and occurs when the microphone is pointed at the external speaker or is close enough to pick up the speaker output. This may be remedied by using a unidirectional microphone, making sure that it is pointed away and as far from the speaker as functionally possible. Another option is to use a headset with an attached microphone.

 

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