Help – My PC Won’t Boot! A Troubleshooting Guide

After spending thousands of dollars on brand new hardware the dang computer won’t even boot. Before you breakout the sledgehammer or start panicking, read this guide to help you troubleshoot this common problem. The fans are spinning and everything looks as though its functioning correctly, but nothing comes up on the monitor.

After spending thousands of dollars on brand new hardware the dang computer won’t even boot. Before you breakout the sledgehammer or start panicking, read this guide to help you troubleshoot this common problem. The fans are spinning and everything looks as though its functioning correctly, but nothing comes up on the monitor.

First of all, make sure the monitor is plugged in (both the power cord and cable into your PC) and turned on. If that does not work, have no fear – there are plenty of other ways to fix this problem. Here is a list of possible solutions:

Check and make sure everything is plugged in correctly.

That includes the power cable going into the power supply and the monitor cable. When checking the power cable make sure that the switch is turned on, too. Take a look inside the case, too. Make sure all wires are connected tightly, especially the ATX power cord plugging into the connector on the motherboard.

Additionally, take a quick look at the ATX power connector itself. Sometimes on cheaper connectors, the pins (and the wires) get pushed out the back of the socket. The pins/wires on the ATX power connector may not even be inside the ATX power connector socket. Also, make sure the power supply’s switch is turned to the on position.

Next, check and see if everything is seated correctly.

The video card should be pushed in all the way and locked into place (some AGP slots do not have a lock). Also, the RAM might look as though it’s in place, but take it out and put it back in just to make sure. In addition, check the contacts on the bottom of the memory and the video card for fingerprints, smudges and dirt. Clean the contacts to ensure proper connection between the slot and the card/memory.

Listen for beep codes.

These codes can be very helpful in telling you exactly what the problem is. You must have your PC speaker plugged in to hear anything, verify that you have already done that. Consult your motherboard manual to find out what kind of BIOS you have. Here is a detailed list of beep codes and their meanings:

These codes are a little more detailed and confusing than the AMI beep codes. Three sets of beeps are produced – for example, 1 -pause- 3 -pause 3 -pause. This is a 1-3-3 combination and each set is separated by a brief pause. Listen to the order of the beeps and pauses carefully – count them twice if you have to.

Try disconnecting any non-essential components, including modems, network cards, hard drives, CD ROMs.

The computer should boot up fine with just RAM, processor (with heatsink attached) and video card installed. If removing all these non-essential parts makes the computer boot up, then you know something that was removed was causing the problem. Use the process of elimination to find out which part was causing the problem.

Try resetting CMOS.

Many times the problem is that simple to fix, once you find the correct jumper. Before you start, make sure your computer is unplugged and the power supply is switched off. Frequently, the reset CMOS jumper is labeled as, “jp1“, “reset CMOS” and “JBAT1“. If you can not tell which jumper it is, consult your motherboard manual.

Simply move the shunt (a little removable piece) off pins 1-2 and move it to pins 2-3. By placing the shunt on pins 2-3, you are completing a circuit. This circuit erases all the settings you changed in CMOS and sets them back to factory defaults. Leave the pins shorted for about 10 seconds to be safe.

Another method of resetting CMOS is removing the motherboard battery and then putting it back a few seconds later. The battery is a little metal circular object – simply pull back the tab and pop it out. Frequently, the reset CMOS jumper is near or next to the battery. Sometimes changing a setting improperly can cause a computer not to boot up, so if that’s the problem, this remedy should cure it. Make sure that when you try to turn your computer back on that the jumper is not still set to Clear CMOS.

A few motherboards require a fan to be plugged in to the CPU fan header which is often labeled on the motherboard’s PCB as “Fan 1” or “CPU Fan”.

The CPU fan header is usually located right near the processor. It takes a 3 pin connector. Plug in any fan to that header. Very rarely this will actually fix the problem, but it is worth a try.{mospagebreak}

Another possibility is that the “on” switch is broken.

Initially, make sure the on switch is plugged into the right place on the motherboard. If it still doesn’t work, try touching the pins with the tip of a screwdriver. Remember to consult the motherboard manual before attempting this method. Make sure you are absolutely sure which pins to short with the screwdriver – shorting certain (wrong) pins could turn out to be disastrous. That’s how a computer can be turned on without an “on” switch. If that works, then you probably need to replace your “on” switch.

Standoffs beneath the motherboard could also be the culprit.

Un-mount and remove the motherboard from the case. Test it from on top of the motherboard box or another non-metal surface. If it works, simply re-mount the motherboard and it just may work, but if it does not, try removing a standoff or two or add washers in between the standoffs and the board.

Also, make sure the heatsink is contacting the core of the processor correctly.

If there is not a proper contact, then it’s possible that the Anti-Burn/Thermal Protection on the motherboard is shutting the computer down or not letting it start up. Try reapplying thermal grease. I prefer a name-brand like Arctic Silver instead of a no-name junk brand.

If all else fails, start swapping out parts.

Try a different video card, memory, processor, power supply and/or motherboard. Get the computer to boot up or at least beep.

Here are some helpful sites that might aid you in fixing your computer:

Abit
Asus
Chaintech
DFI
ECS
Epox
Giga-Byte
Intel
Iwill
Jetway
MSI
PC Chips
Shuttle
Soltek
Soyo
Tyan

Hardware Central’s Beep Code Information
PC Hell’s Beep Code Information
Tech ARP’s BIOS Guide
Overclockers Forums: How to solve your computer EMERGENCY!

In addition, I have included a little checklist below, so as you go along in trying to fix your computer, you can rule out what is not wrong:

1. Make sure everything is plugged in correctly and the power supply switch is on.
2. Make sure all the hardware is seated properly.
3. Check for Beep Codes.
4. Disconnect all non-essential components.
5. Reset CMOS.
6. Check to see that there is a fan plugged into CPU Fan Header.
7. Test the “on” switch.
8. Make sure standoffs are not shorting out the motherboard.
9. Make sure the heatsink is contacting the core correctly.
10. Swap out parts and test for what is causing the problem.

I will end this guide like I end my forums posts, best of luck to you in fixing your computer. It may not be easy, it might even take a long time, but in the end you will fix it. If you have any questions or comments about this guide, post them in the forums.

Be sure to check out the alternate location of this guide at Overclockers Forums HERE.

-Matt (mdcomp)