Fixing Computers

Motherboard 

Some things to check when motherboard fails.

1. Are the minimum things needed to boot present? A barebone working system includes a motherboard, processor, a full bank of memory, a video card, and a drive to boot off of. If these things are not there, it will not work. Are these things all properly connected? 
2. Try removing everything else one by one and try to narrow down the problem. 
3. Are the jumper settings correct? You must set jumpers correctly for processor type, speed, voltage, bus speed, etc. Consult the manual. 
4. If you tried to streamline the BIOS, return all settings to default. 
5. Is the motherboard in good shape? Any cracks, bent pins? 
6. Is there enough power? If you are adding more or newer components to an old system, your power supply might not be powerful enough. A mainstream power supply is 230 or 250 watts. 
7. Troubleshoot other hardware in computer. 
8. Check around the net and see if there is a known "bug" on your particular motherboard. Check the manufacturer's web site to see if there are any updates for it. 
9. If you recently had a bad rain storm with lightning and have no surge protection on the computer, you could also have a fried motherboard due electric surge.

CPU 

If a PC's processor fails, it can only be replaced. However, most problems that appear to be processor problems are usually a problem with another component. What may show up as a processor problem is more likely a problem with either the cooling of the processor or the system, the power supply, or a compatibility issue between motherboard and chipset.

Here are the most common symptoms that a processor is about to fail.

1.  The PC will not boot.
2. The PC does boot, but will not start the operating system.
3. The PC crashes during startup and if it does boot, crashes frequently when running applications.
4. The PC suddenly has POST parity error problems in many devices.
5. The PC locks up after a few minutes of operation.

If you experience any of these problems, check the cooling on the processor and on the system, clean the inside of the case, and check the motherboard's power connection.

Memory 

Knowing when a memory problem happens is very valuable information. A memory problem happens during startup is a much different problem than one that happens when an application is running and is resolved quite differently. Memory Problems can occur in these situations.

1.  The first time a new PC is started This common problem is caused by the rigors of shipping a PC. The memory chips may need to be reseated or may be missing. A problem that appears to be memory-related could also be a bad motherboard.
2. Immediately after new memory is installed Check the part numbers and speed of both the new and the old memory modules. Verify the memory was properly installed or configured in memory banks.
3. Immediately after new software or operating system is installed Later versions of applications and operating systems can require more memory than their older versions. New software, especially beta versions, can have several bugs that produce memory errors on the PC. You can try to uninstall, reinstall or check for updates on the softwares.
4. Immediately after hardware is installed or removed When new hardware is installed incorrectly or a connector that is connected to the motherboard is dislodged or missing, the errors that result can appear to be memory errors. Check the cables and connectors.
5. For no apparent reason If a PC has been running okay and suddenly begins having memory probelems, reseat the memory modules and check for corrosion on the contacts of the memory modules and slot connectors. If the PC is running too hot, it may have danaged the motherboard, memory, or processor to the point of errors.

To do troubleshooting on the motherboard, CPU, RAM using flowchart, please refer to the chart below. It is a detailed flowchart on motherboard, CPU, RAM failure taken from "Computer Repair with Diagnostic Flowcharts".