Use these following ten rules when repairing or trouble-shooting a computer :
Gather together your toolkit and any necessary documentation for that specific computer.
Check for power FIRST, before doing anything else. 10 – 15 percent of all trouble calls are for nothing more than a popped circuit breaker or a loose plug. Check these things BEFORE doing anything else.
Check your external connections to the computer. Specifically, check the mouse, keyboard, monitor, modem and/or printer cables, making sure that all are secure and in the right sockets.
If the computer is still malfunctioning, go ahead then and open the case. Check to see that all of the cards are fully pressed down into the bus connections, that any socketed chips are fully pressed into their sockets, and that all cable connections are fully attached. Make sure that the drive cables are attached so that the colored stripe on the cable is positioned next to pin 1 on the connector.
Clean any dust or foreign material out of the case while it is open. Dust can cause overheating problems and electrical shorts. Sometimes, insects will nest inside the case as well. All of this needs to be cleaned out before you close up the case. Use compressed air and non-conductive materials to clean out the inside of the case. Take precautions to avoid inhaling excess dust, and consider using protective eyeware if necessary.
Try to boot the computer to the hard drive, or to a bootable floppy disk if necessary. Sometimes the hard disk will become corrupted by a user, or by a virus. If you can’t access the hard drive directly, have a bootable floppy disk available. This bootable floppy disk should have a copy of your CONFIG.SYS and AUTOEXEC.BAT files on it, as well as any drivers necessary for devices like your sound card, CD-ROM drive, and mouse. Have a good disk diagnostic program available (SCANDISK, Norton Utilities), and a good virus checking program as well. If your data is severely damaged, you may need to wipe the disk and reload the data from original or backup disks.
Check the CMOS setup program, and correct any configuration problems. If the information in CMOS RAM about your PC’s configuration has been changed, or if the battery has died, your computer will not boot correctly, or it will not recognize certain components. Keep a copy of your setup program information handy, so that if something changes, you can correct the problem. batteries should last about 2-3 years.
Look for unwelcome changes. Someone may have turned the brightness down on a monitor, or the LAN staff may have changed your PC’s configuration without your knowledge (or approval), or an installation program may have corrupted something in your software. Look for recent changes in your system’s operation. You may need to run an uninstaller program to remedy software-related problems.
Isolate the problem to one piece of hardware, or one software package. The problem you are encountering may occur only in one software package, which means the problem has a very limited scope. If the problem occurs in all programs, then it’s a systemic problem. Refer to software and operating system manuals as needed, and have the original software disks available, in case a driver needs to be reloaded. If the system just won’t fire up, remove all nonessential components, and see if you can cause the problem to re-appear by re-installing components one-at-a-time. This process is usually quite helpful in trouble-shooting even the most stubborn problems.
When all else fails, read the manual. There may be something unique about your computer that requires special attention as directed by the manufacturer.