Troubleshooting Computers: The Basics
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Troubleshooting computers can be a little frustrating and a little tricky. With so many parts and software installed, any number of things can go wrong. But when (not if) something happens, this is the best opportunity for you to learn-of course provided that you have a few basics under your belt. Nothing beats experience. The more you do it, the better you become, and the more your confidence grows. And the best part, you will save yourself a lot of money.
There are many things that can go wrong with a computer. Here I try to cover the basics to get you going in the right direction.
OK, so where do we begin?
Well let's start with an important tip: When troubleshooting computers always start with the simple stuff. By that I mean there's a tendency to assume that when something happens it's always due to a major problem, when all it could be is a loose cable or something else minor. I have been guilty of this myself. Check the easy things first!!!
Now the real challenge is deciding whether a symptom is hardware or software related. A lot of times this comes through trial and error. Don't be afraid of misdiagnosing a problem. It's going to happen. Just keep at it.
Issues During the POST
When you power on your system, the power supply sends a signal to the CPU, which receives instructions to go to the BIOS to start the boot process. Part of this process is the POST (Power On Self Test). Problems arising at this stage are almost always hardware. During the POST, devices are found and checked for errors. If everything is fine the motherboard speaker will usually sound a single, short beep and move on to loading the operating system. If something occurs you will hear some type of beep or see an error message on the screen. BIOS manufacturers have different beep codes so you will have to know which BIOS your system is using. Phoenix and AMI are the two primary makers. Award BIOS was bought out by Phoenix in 1998. You can find the type of BIOS you have by either turning on your computer (assuming of course it comes on) and looking at the top left of the screen, opening the case and looking at the BIOS chip, consulting the motherboard manufacturer or the company that built your computer.
Whichever BIOS you have, if the beep code indicates a memory or video card problem the usual solution is to check to see if they are fully seated in their slots or to replace the part. If using built-in video then it could be the motherboard. If it's a CPU beep code your processor might be overheating. Some BIOS setups are set to shut the computer down if the processor is too hot. A malfunctioning processor fan can could be the culprit. Turn off the computer and remove the case. Turn the computer back on and see if the fan is working or running slowly. If it's the fan, replace it. If not, remove the processor and see if there's any physical damage to it. Keep in mind that you will not always see physical damage on a bad CPU.
If you don't hear any beep, more than likely it's a failing power supply or motherboard.
Both AMI and Phoenix have many beep codes, many of which rarely occur. To see the list visit one of the links below.
http://www.ami.com/support/doc/AMIBIOS8_Checkpoint_and_Beep_Code_List_PUB.pdf
http://pcsupport.about.com/od/fixtheproblem/tp/phoenix-beep-codes.htm
There are many things that can go wrong with a computer. Here I try to cover the basics to get you going in the right direction.
OK, so where do we begin?
Well let's start with an important tip: When troubleshooting computers always start with the simple stuff. By that I mean there's a tendency to assume that when something happens it's always due to a major problem, when all it could be is a loose cable or something else minor. I have been guilty of this myself. Check the easy things first!!!
Now the real challenge is deciding whether a symptom is hardware or software related. A lot of times this comes through trial and error. Don't be afraid of misdiagnosing a problem. It's going to happen. Just keep at it.
Issues During the POST
When you power on your system, the power supply sends a signal to the CPU, which receives instructions to go to the BIOS to start the boot process. Part of this process is the POST (Power On Self Test). Problems arising at this stage are almost always hardware. During the POST, devices are found and checked for errors. If everything is fine the motherboard speaker will usually sound a single, short beep and move on to loading the operating system. If something occurs you will hear some type of beep or see an error message on the screen. BIOS manufacturers have different beep codes so you will have to know which BIOS your system is using. Phoenix and AMI are the two primary makers. Award BIOS was bought out by Phoenix in 1998. You can find the type of BIOS you have by either turning on your computer (assuming of course it comes on) and looking at the top left of the screen, opening the case and looking at the BIOS chip, consulting the motherboard manufacturer or the company that built your computer.
Whichever BIOS you have, if the beep code indicates a memory or video card problem the usual solution is to check to see if they are fully seated in their slots or to replace the part. If using built-in video then it could be the motherboard. If it's a CPU beep code your processor might be overheating. Some BIOS setups are set to shut the computer down if the processor is too hot. A malfunctioning processor fan can could be the culprit. Turn off the computer and remove the case. Turn the computer back on and see if the fan is working or running slowly. If it's the fan, replace it. If not, remove the processor and see if there's any physical damage to it. Keep in mind that you will not always see physical damage on a bad CPU.
If you don't hear any beep, more than likely it's a failing power supply or motherboard.
Both AMI and Phoenix have many beep codes, many of which rarely occur. To see the list visit one of the links below.
http://www.ami.com/support/doc/AMIBIOS8_Checkpoint_and_Beep_Code_List_PUB.pdf
http://pcsupport.about.com/od/fixtheproblem/tp/phoenix-beep-codes.htm
No Operating System Found or Similar Message
After the POST and listed information the BIOS checks the boot device for the master boot record (MBR), which tells where the operating system (OS) is. A drive set to boot with no operating system will produce an error, so make sure your system is set to boot from the right device. Go into CMOS and look under the BOOT menu to see if the proper boot order is listed. (Again, depending on the BIOS, there are various ways to enter CMOS. It's listed at the bottom of the screen soon after you turn on the computer. Most of the time it's by pressing DEL, F1, or F2). In many cases the DVD drive is first on the list followed by the hard drive(s). That's OK. If the DVD drive is empty BIOS skips it and starts looking at the hard drives. If there is a non-bootable DVD in the drive, remove it. Your boot drive should be the first option or second (If DVD drive is first). Once found, the OS begins to load.
After the POST and listed information the BIOS checks the boot device for the master boot record (MBR), which tells where the operating system (OS) is. A drive set to boot with no operating system will produce an error, so make sure your system is set to boot from the right device. Go into CMOS and look under the BOOT menu to see if the proper boot order is listed. (Again, depending on the BIOS, there are various ways to enter CMOS. It's listed at the bottom of the screen soon after you turn on the computer. Most of the time it's by pressing DEL, F1, or F2). In many cases the DVD drive is first on the list followed by the hard drive(s). That's OK. If the DVD drive is empty BIOS skips it and starts looking at the hard drives. If there is a non-bootable DVD in the drive, remove it. Your boot drive should be the first option or second (If DVD drive is first). Once found, the OS begins to load.
Another cause for this message is that the master boot record itself can become corrupted.
Here is a link to a quick tutorial on how to fix a damaged MBR with an XP or Vista CD. http://www.slowpctips.com/windows-help/repairing-the-mbr/
Here is a link to a quick tutorial on how to fix a damaged MBR with an XP or Vista CD. http://www.slowpctips.com/windows-help/repairing-the-mbr/
Devices Not Listed in BIOS
Immediately after the POST is performed information about your computer is listed on the screen, including your drives. If you don't see a drive listed, go back and make sure they are installed properly and that cables are firmly connected.
Immediately after the POST is performed information about your computer is listed on the screen, including your drives. If you don't see a drive listed, go back and make sure they are installed properly and that cables are firmly connected.
Optical & Hard Drives-------------------------->
100110010111
7D2F:FA62
111111111111
4BBC:E101:A240:3123
0010001101110
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