How To Troubleshoot a PC That Won't Turn On

I saw this article and really liked it and is pretty informative. I do disagree in the order of some of the steps. Steps 6, 7 and 8 seem to assume that your comfortable opening, changing things around inside the case and have some technical knowledge of what's inside. The newbie, average or casual user is probably not going to be comfortable opening the case. No more than I would be trying to explain to Bill Gates how Windows works. Even in my case I'd like to save opening the case as a last resort item. My advise would be to skip 6,7, and 8. Go ahead to 9, 10 and 11. If your still having problems at that point perhaps go back to 6,7 and 8. If your not comfortable opening your PC have a tech savvy friend or perhaps a technician who could help you in this matter.Proper precautions have to be taken when opening the case to prevent ESD(electro static discharge) which could cause more problems than perhaps you already have.






How To Troubleshoot a PC That Won't Turn On
From Tim Fisher,
Your Guide to Focus on PC Support.
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It's a dreadful way to start a day - you press the power button on your PC and nothing happens. Do not fear because all may not be lost! Follow these simple steps to determine why your computer won't turn on.

Note: It is very important to troubleshoot any issue beginning with the most likely and easily testable problem so be sure to follow these steps in order.

Difficulty: Average

Time Required: Anywhere from 10 minutes to a few hours depending on why the computer won't turn on
Here's How:

1.As silly as it may sound, the number one reason why a computer won't turn on is because it wasn't turned on! Before starting a sometimes time consuming troubleshooting process, make sure you've actually turned on both the computer case and the monitor using the power switches on the front of both.

2.Many computers have power switches on the power supply, located on the back of the PC's case. Check this switch, often called the rear power switch, and make sure it is turned on and that the correct voltage is set and then attempt to power on your computer again.

Tip: On is indicated by the "I" symbol and off is indicated by the "O" symbol.

3.Check for loose PC and monitor power cable connections. A loose or unplugged power cable is one of the top reasons why a computer doesn't turn on.

4.Perform a "lamp test" to verify power is being provided. Your computer isn't going to turn on if it's not getting power so you need to make sure that the power source is working properly.

5.A damaged power supply could be preventing the PC from being properly powered, an excellent reason why the PC won't power on.

Do a quick test of the power supply by holding your hand behind the power supply fan located at the rear of the case. If the power supply is working, you should feel air from within the case blowing against your hand. If not, you may need to replace the power supply.

Tip: Is the power light on the front of the computer's case on? If you've turned the power switch on but the light is off, this is another good indication that the power supply is the cause of this issue.

6.Over time, internal components and the cables that connect them can wiggle loose which can often time result in a computer unable to power on. Try reseating the following and then try to power on the PC again:
* Reseat the internal cables
* Reseat the memory modules
* Reseat the video card
* Reseat other expansion cards

7.Reseating the CPU may also be necessary but should only be attempted if the reaseating of all other components is not successful. This is due to the fact that this process is a little more involved and can run a small risk of damage to the CPU (this isn't a big concern if you're careful, so don't worry!).

8.Check for causes of electrical shorts in the computer case. This is often the cause of the problem when the computer powers on for a second or two but then powers off completely.

9.Hearing beeps? You haven't gone mad - your computer may be using a beep code to tell you exactly what's wrong! Troubleshoot the beep code and service the computer as necessary.

10.Most monitors have a small light next to the power button that can change between various colors. If the screen is blank, this light is your main source of information about the monitor.

If this light is not on at all, double-check the power switch and connections (Steps 1, 2 and 3) and also make sure the monitor cable is securely plugged in to the video card port on the back of the computer case. If the light is still off, replace the monitor. If it comes back on, try starting your PC again - a loose or unplugged monitor cable may have been the issue all along.

11.An amber or yellow power light simply means that the monitor is not receiving any information from the computer. In and of itself, this doesn't tell us much.

On the other hand, if the light is amber or yellow, the computer power light is on, and the hard drive is active (making normal sounds and hard drive activity light on the computer case is blinking), the computer is probably starting normally but the video card is not sending information to the monitor. Replace the video card.

Beep codes usually sound when a video card has malfunctioned (Step 9) but this is not always the case.

Tips:

1.Still can't get your PC to turn on? Let a community of PC support enthusiasts help out! Post the details of your problem in the Focus on PC Support Forums.

More How To's from your Guide To Focus on PC Support

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