Troubleshooting: Common First-Boot Problems

Common initial boot problems:

This appendix deals with pretty much everything that could go wrong in your initial boot.  For each common problem, possible solutions are sorted by the likelihood of the solution and the ease of remedy.  For example, if the computer won’t turn on, I won’t first recommend the cumbersome task of removing and reconnecting the motherboard, I’ll suggest something like checking to make sure the power cord is plugged in.

If you press the power button and nothing happens, the computer just sits there, cold and lifeless, here is a hierarchy of possible solutions.

1. Check to make sure the power cord for the computer is plugged into both the power supply and a wall outlet or surge-protection power strip.  If you’re using a power strip, make sure it’s turned on.
2. Check the back of the power supply.  Is the red switch set to 115V if you’re in the United States or 230V outside the U.S.?  If not, correct it and try to power on again.
3. This next step is probably the most common downfall.  Check your front panel connections, specifically to make sure the one labeled “Power SW” is in the correct location.  Normally you would need to refer to the motherboard manual under “Front Panel Connections,” but since we’re using identical motherboards, we can cheat.  Find set of pins labeled JFP1.  According to the diagram, the power switch connector should join pins 6 and 8, which are located here. Since it’s a switch, it doesn’t matter which end connects to pin 6 or pin 8, as long as they’re connected.

4. If those steps all fail, try resetting the BIOS.  To do this, Locate the line of 3 pins with a jumper attached to two of them (in the bottom-right corner of the motherboard).  The motherboard manual will tell us that when the jumper is shorting these two top pins (pin 1 and pin 2), the CMOS will retain the BIOS data.  When it is connecting the bottom two pins (pin 2 and pin 3), the CMOS will clear all the data.  Remove the jumper from pins 1 and 2 and replace it onto pins 2 and three.  I usually wait a few seconds to make sure the memory is cleared, and then replace the CMOS jumper to pins 1 and 2.  The BIOS is now (usually) set to its fail-safe defaults.

If, when you press the power button, the case speaker makes beeps other than a single short beep, something is wrong.  Power off your computer and go through this checklist:

1. If the beep code is one long beep and two short beeps, that’s a signature for a video card problem.  Most likely it was improperly seated in its slot.  Unplug the power cord, pull out the video card, and reinsert it.  If you still get that beep combination after that, try a different video card (preferably of a different model or even manufacturer) because that one is most likely the problem.
2. Check the voltage switch on the power supply.  Ensure it is set to 115V if you’re in the US, or 230V if you’re elsewhere.
3. Check your RAM DIMMs.  Unplug the power cord from your power supply and take the RAM out of its socket.  Inspect for physical damage and replace it if none is found.  Be sure the RAM is fully inserted into the socket and both clips are locked (PICTURE EXAMPLE).  Improperly installed or erroneous RAM is the cause of most beep codes. Tip: If you’re using more than one stick of RAM, try booting with just one stick installed.  If you get the same error, switch out the stick to try to narrow it down to one erroneous stick.
4. Reset the BIOS. To do this, Locate the line of 3 pins with a jumper attached to two of them (in the bottom-right corner of the motherboard).  The motherboard manual will tell us that when the jumper is shorting these two top pins (pin 1 and pin 2), the CMOS will retain the BIOS data.  When it is connecting the bottom two pins (pin 2 and pin 3), the CMOS will clear all the data.  Remove the jumper from pins 1 and 2 and replace it onto pins 2 and three.  I usually wait a few seconds to make sure the memory is cleared, and then replace the CMOS jumper to pins 1 and 2.  The BIOS is now (usually) set to its fail-safe defaults.
5. Ensure the CPU power is connected correctly.  You should NOT use the leftover 4-pin connector from the 20-pin ATX power connector.  You SHOULD use the 2-pin by 2-pin Molex connector shaped similarly but with a clip on the plastic Molex and 2 black wires and 2 yellow wires.  Ensure it is locked in by lightly tugging on it.  If it disconnects with a light tug, plug it in ensuring that the clip locks in place securely.
6. If the computer is still beeping abnormally after all that work, there is most likely something wrong with the motherboard and you’ll need a replacement.

Tip:  For help on beep codes go to www.computerhope.com/beep.htm.

If, when the power button is pushed, the computer powers on, but it powers itself off within a few seconds, the number one cause is CPU overheating.  Most of the new motherboards will automatically power off the computer if it detects the CPU is exceeding an ultra-high temperature (like 80 degrees Celsius).  The CPU may be overheating for a couple reasons.

1. Does the CPU fan run when the computer is turned on?  If it doesn’t the most likely cause is that it is unplugged.  It may have come unplugged while the rest of the computer was being assembled and cables were being routed.  It may also be plugged into the incorrect header.  For this tutorial PC, our CPU fan uses a 3-pin power connection.  If this is plugged into the 4-pin power header on the motherboard, it might fit, but it won’t work.  Our motherboard came with a 3-pin and a 4-pin fan connector, respectively on the top-left and top-right of the heatsink socket.  The 3-pin fan should be connected to the 3-pin socket on the top-left of the heatsink.
2. Is the heatsink clamped down properly?  Each of the four corners have clips that need to be attached to the socket.  The beige handles also must be pulled across to lock it down into place.  Their final position should have the left one pointing down and the right one pointing up.  Sometimes the clips detach during the lock-down, which happened in my case.  To offset the force on the clips during this process I pushed down on heatsink and fan with one hand while the other swung the lever.  I had to do this for both sides.  If you’re using this guide for reference on a different set of components, specifically a different socket type, the method for attaching the heatsink will be different, and you should follow the instructions found with your heatsink to make sure it is attached properly. 
3. The only other problem I’ve had installing a heatsink was while using a Socket 775 board and heatsink.  The motherboard I was using had transistors (tiny soup-can-shaped pieces attached around the motherboard) fixed very close to the processor.  I ended up mounting the heatsink facing the wrong direction and it was tightened down on top of the transistors.  A side view revealed the heatsink was crooked and not even touching the processor.  I had to rotate it around until it fit correctly.  This is another reason to install the CPU and heatsink onto the motherboard before you install it into the case.

If you power-on your computer and the fans spin, but nothing else happens (no beeps, nothing displayed on the monitor), there are quite a few things to check.  After each step, try powering-on again.  We’ll start with the easiest remedies and work up the most time consuming.  I gathered some of the items in this list from www.mysuperpc.com/build/pc_first_boot_common_problems.shtml. 

1. Try resetting the computer by pressing the reset button.
2. Clear the CMOS, first the normal way described above.  If it still doesn’t work, try removing the CMOS battery (after unplugging the computer power cable) for a few seconds, then try booting again. If this doesn’t work, try leaving the battery out for at least 15 minutes, which will ensure there is no charge left the system to retain that possibly corrupt data.
3. In our tutorial system, the power supply has more than enough power for all of our components, however, if you’re using this list for reference on a high-end PC, the cause might be insufficient power.  If you’re trying to use the newest processors and graphics cards on the power supply that came with your case, you might need to consider buying a new power supply.  550 watts should cover just about anything on the market today, but keep in mind that a brand name power supply is just as important from a reliability standpoint.  You can purchase an awesome power supply for around $50, so if you’re building a fast machine, I recommend using a top-of-the-line power supply to back it.
4. Since your case speaker didn’t beep, it may not be plugged in correctly.  Verify the connection by looking at this picture.  If you connected this pin wrong, you may have connected some of the others wrong as well.  Try to make it match the pictures in the connection section, or if you’re not building the tutorial computer, check your motherboard manual for the correct front panel configuration.
5. Take hold of the box by the front and back panels and, with the open side facing up, gently tip and shake the case.  The main thing we’re listening and looking for is something (most likely a screw) skidding around.  The screw may be causing a short in the system, which would no doubt prevent the computer from booting. If you hear something skating around on the steel plate, do whatever you need to do to remove it.  This could include taking the other side panel off or even taking off the motherboard if the object is trapped beneath.
6. Try taking the memory out and putting it back in, making sure both clips click in.
7. Visually inspect your processor; it might be nuked.  If something was wrong with the cooling (heatsink/fan) on your processor, it may have fried the chip.  If the chip is fried, you may be able to see burn marks on the chip itself.  This means you’ll have to get a new one.
8. This is very often the cause of the problem but is very labor intensive to check, which is why I saved it for last.  Your case may be creating a short with your motherboard.  To test this, you’ll need to take the motherboard out of the case.  Leave the all the connections to the power supply and case intact, and leave the memory and processor on the board.  I recommend setting it on the anti-static bag that the motherboard came with.  You want everything connected that was connected inside the case, with the only piece missing being the motherboard screws.  At this point, power it on and see what happens.  If something actually appears on the screen and you hear the speaker beep, whether it boots up error-free or not, you have an issue with the case (or more likely a motherboard screw) shorting out your computer.  Re-installing the motherboard into the case and trying to boot up might work, but if it doesn’t pick up some non-conductive (rubber) washers (RadioShack will most likely have them) and use them between the motherboard and the screw.  If it still doesn’t work, add a washer in between each screw hole and motherboard mount (behind the motherboard).
9. If all else fails, try taking your mystery box to a local computer repair shop.  They can typically run diagnostics tests for $50-$75.  If you find out what part is at fault (and you didn’t cause it), you can typically return it to the store you bought it from.  This process is called RMA, and details should be available on your receipt or on the company’s website.

If the power light and/or hard drive activity light on your case is not working, this is a relatively simple fix.

1. First open up your motherboard manual to the page with the front panel connections (page 9 for the tutorial).  Verify that the HDD_LED and Power_LED cables are connected to the correct set of pins.  If their positioning is not accurate, correct it, and boot the computer to see if it works.
2. If they are plugged into the correct pins, but one or both are refusing to light up, flip the non-working connector 180 degrees.  LEDs are sensitive to polarity, unlike the case speaker and switches, so this should fix the problem.  If it still doesn’t work, you can call the motherboard manufacturer and describe the situation.

If you’re building a computer with a floppy drive and the light is casting steady beam from the moment you turned on your computer, this is also a simple fix.  Simply unplug the ribbon cable from the back of the floppy drive, flip it 180 degrees, and plug it back in.