PC Will Not Boot

Whether you’re a novice or an expert PC technician, we’ve all had an experience when a new PC would not boot. There’s no worse feeling than pushing the power button on the front of a new machine an hearing absolutely nothing. This article will focus on some of the common problems with new builds and help to reduce the computer troubleshooting time when diagnosing problems with your new computer.

Take A Quick Visual Of The Computer

You should have already done this before trying to power up the PC, but a lot of novice PC builders will skip this step in anticipation of powering up their new machine. This step may save you time and money. First, triple check to make sure the CPU is sitting flat on the motherboard socket. It’s probably hard to tell because of the heat sink, but if the entire CPU and heat sink combo looks skewed, then chances are it’s not installed properly. Next, go over the IDE cables and the thin wires running from the power and reset switches to the motherboard. While the IDE cables are keyed, it’s quite possible to get those case wires backwards or completely. Lastly give the PC a little shake. Make sure an errant screw didn’t fall behind the motherboard during the install. This could blow the motherboard or cause the system to go to ground.

Computer Hardware Troubleshooting

When a new PC will not boot, a good place to start is the power supply. Is the machine getting power? If there is no fan activity at the rear of the power supply, then the power supply isn’t working. First, check the wall socket and power strip to make sure power is actually being supplied to the computer. If there is power to the outlet, confirm that the | / O lever in the back is set to |. Then confirm that the voltage is set to 110V in the USA or 220V in countries that require that setting. If you have a voltmeter, you might want to consider testing the power supply. Refer to the pin out chart for the correct power supply voltages.

Troubleshooting Video Cards

If the system powers up, but you get nothing on the screen, the video card may be the culprit. First, confirm the video cable is secured to the video card’s output. If the motherboard has built in video, and you’re using a PCI-E or AGP card, make sure the cable is secured to the correct port. Also, check for bent pins on the connector and confirm the monitor works and the brightness controls are set correctly. Do you hear any beeps? If so, refer to our BIOS beep code chart. It’s always a good idea to reseat the RAM and video card when you get the “No Signal Displayed” message on the monitor.

Dead Motherboard or CPU

Improper installation of the motherboard and CPU can cause instant failure. We like to install the CPU and RAM modules on the motherboard before installing the motherboard in the case this is because it sometimes requires some effort to get the heat sink seated properly on the CPU. The CPU itself should slide effortlessly into place and lock without any problems with the lever. If you require resistance when installing the CPU, make sure the CPU’s pins are properly aligned to the socket on the motherboard. Apply the correct amount of thermal grease or tape as recommended by the manufacturer, then install the heat sink. The heat sink should rest flatly on top of the CPU.

As for the motherboard, refer to the manual about each of the connections to the case. A common problem area are the standoffs between the case and motherboard, and the connection of the thin wires from the power and reset switches to the motherboard.


You will often receive a BIOS beep code when there is a hardware issue with the PC. You should determine the BIOS residing on the motherboard by physically looking for the BIOS chip on the motherboard. Look for something like AMI-BIOS, AWARD BIOS or PHOENIX. Refer to our BIOS Beep Code Chart when diagnosing beep code errors. This will often lead you quickly to the source of the hardware problem.

In Conclusion

While these new computer installations can be frustrating, it’s important to take a step back and think before you do more damage. Take a nap or a walk and then look at the problem with fresh eyes. If you need further assistance, please consult our techs on our message boards.


  1. Melva August 11, 2009
    • Dave August 12, 2009
  2. Melanie August 13, 2009
    • Dave August 13, 2009
  3. Melanie August 13, 2009
  4. Jolee M August 14, 2009
    • Dave August 15, 2009
  5. Darla August 14, 2009
    • Dave August 15, 2009
  6. Darla August 15, 2009
  7. vinay barla August 21, 2009
  8. David Vidovic August 25, 2009
    • Dave August 25, 2009
  9. Benjamin BOATENG August 28, 2009
    • Dave August 28, 2009
  10. carolyn August 28, 2009
  11. rama August 31, 2009
    • Dave September 6, 2009
  12. OYO September 4, 2009
  13. nd September 9, 2009
    • Dave September 11, 2009
  14. THERESA NORCZYK September 28, 2009
    • Dave September 29, 2009
  15. Daniel November 12, 2010
  16. Tommy January 22, 2011
    • David Purcell January 24, 2011