# Basic computer troubleshooting



## c_robertson (Aug 22, 2009)

This is intended to be a cumulative message to help people follow basic troubleshooting and as a reference for other threads. This is NOT the definitive answer, but is a good starting point. Administrators feel free to add/modify as necessary.

Note: These are based on the assumption your computer was working in the past week. Not for troubleshooting new builds.
Post is the message(s) you receive in black and white before the OS begins to boot.

No lights, No Screen (worked previously)
•	Power supply tripped – This is common if the PS is becoming faulty or something has shorted the power supply and it has “Tripped”
o	Unplug the cord from the PS (do not use the power stip) and let sit for 5-20 minutes.
•	Not plugged in – 
o	Try something else in the outlet 
o	Check the lights on the motherboard
•	Faulty power supply 
o	Unplug and re-plug all connectors from the power supply to motherboard.
o	Is there any lights on the motherboard lit?
o	Try another power supply (larger not smaller)
o	Purchase/use power supply tester (ebay)
o	Use a meter to check voltages
•	Shorted Board – common problem is Damaged USBs or pinched wires
o	Inspect USB ports ensuring they are not damaged or pins are bent.
o	Disconnect all drives, card readers, USB ports from motherboard and restart
•	Bad Motherboard – Occasionally mother boards fail for many reasons. Fault capacitors or broken traces. If you feel the motherboard is bad, replace it at your own risk. This is an advanced process, not meant for the common user.

Lights, No Screen, No Post – This is a common occurrence for failed video or several other problems and has the appearance that the computer is on. Open case and check fans are actually coming on when the power button is pressed.
•	Monitor is off or unplugged
o	Unplug and re-plug the monitor
o	Ensure the monitor has an amber power button and is on
o	Ensure the monitor cable is not loose or unplugged
o	Use a known good monitor
•	Bad Power supply 
o	Test or replace power supply
•	Test the power supply, replace if necessary
•	Bad Video/Video card
o	Replace the video card (with a known good card)
o	If there is an integrated video plug, connect to that and test.
•	Bios Problem – Occasionally the bios will fail, and there will be no boot, but there should be backlight to the video, or the power button on the monitor will turn green, but not video is displayed
•	Shorted Board – common problem is Damaged USBs or pinched wires
o	Inspect USB ports ensuring they are not damaged or pins are bent.
o	Disconnect all drives, card readers, USB ports from motherboard and restart

Bios/Post, No Windows/OS (error messages) – There may be multiple causes for this, or combinations
•	Faulty power supply 
o	Unplug and re-plug all connectors from the power supply to motherboard.
o	Is there any lights on the motherboard lit?
o	Try another power supply (larger not smaller)
o	Purchase/use power supply tester (ebay)
o	Use a meter to check voltages
•	Shorted Board – common problem is Damaged USBs or pinched wires
o	Inspect USB ports ensuring they are not damaged or pins are bent.
o	Disconnect all drives, card readers, USB ports from motherboard and restart
•	Bad Motherboard – Occasionally mother boards fail for many reasons. Fault capacitors or broken traces. If you feel the motherboard is bad, replace it at your own risk. This is an advanced process, not meant for the common user.
•	Bios Problem – Occasionally the bios will fail, and there will be no boot, but there should be backlight to the video, or the power button on the monitor will turn green, but not video is displayed
•	Memory – Bad memory can cause numerous problems and failures. Replacement is the best test.
o	2 memory slots – With the power off, and the computer unplugged, remove one stick of memory at a time keep one in the left-hand slot at all times
o	4 memory slots (slots are 2 different colors) – Commonly requires 2 memory sticks at one time. The currently populated slots are your “Primary slots” replace the memory with comparable (known good or New) memory.

Windows crashing - This is the most complex problem. It may be caused by software or hardware, or even a combination of the two. Often times, software is damaged by hardware failures
•	Memory – Bad memory can cause numerous problems and failures. Replacement is the best test.
o	2 memory slots – With the power off, and the computer unplugged, remove one stick of memory at a time keep one in the left-hand slot at all times
o	4 memory slots (slots are 2 different colors) – Commonly requires 2 memory sticks at one time. The currently populated slots are your “Primary slots” replace the memory with comparable (known good or New) memory.
•	Faulty power supply 
o	Unplug and re-plug all connectors from the power supply to motherboard.
o	Is there any lights on the motherboard lit?
o	Try another power supply (larger not smaller)
o	Purchase/use power supply tester (ebay)
o	Use a meter to check voltages
•	Hard drive failures – Hard drive failures is difficult to diagnose
o	Open “My Computer” (“Computer” for vista and Win7 users) and right click on the C: drive (your primary drive)
o	Select properties
o	Click on “Tools” tab
o	Click the “Check now” button in the “Error checking” section
o	Select “Automatically fix file system errors” & Scan for and attempt recovery of bad sectors”
o	You will receive a message to restart the computer.
o	Restart the computer and watch messages for bad sectors or files
•	Heat problems – Download two program from another computer and allow this program to cool. Heavy load and speedfan
o	Start computer from cool state
o	Install and run Heavy load and Speedfan
o	Check temperatures with speedfan and watch for overheating
o	If temperatures does not rise, run heavyload and execute and watch for overheating.
•	Damged OS – Numerous problem can cause damage to the OS or simply program such as malware or virus can cause these problems. Even some programs or settings cause periodic shutdown. At this point refer to the forum for more help.
o	Please remember to provide full specifications for the system you are using;
o	Manufacturer, model number, OS, etc.


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