Troubleshooting a custom built computer


One of the downsides to building your own computer is that if something goes wrong, you’re the tech support. If you’re having trouble with a specific component, you might be able to ring the manufacturer for help but unless you know what’s causing the problem, it can be a bit of a headache. This guide will help you with where to start if your PC won’t.


Error codes


Error codes and beep codes are ways that motherboard manufacturers use to let you know there’s a problem, and what that problem is. Beep codes were used more on older machines, error codes are the more common choice now.

Unfortunately, there isn’t a universal list of the codes and their meanings, because they’re different for each manufacturer. You’ll need to have a look at the paperwork you got with your motherboard to find out what your error code means. We’ve had a look at some individual parts below, so if your error code relates to one of them, you could find the fix here.

error codes



Checking components


You should have tested all your components before they made their home in your case, but that doesn’t mean one of them isn’t to blame. Let’s have a look at what you can do to figure out the problem.



There's quite a few power plugs that need to be connected, and it can be quite easy to miss one of them. Check through them all and make sure they're seated properly. The problem could be as simple as a loose cable.

power supply




When you install the CPU, the cooler should sit flush with the top of the chip. The screws that hold it in place should be tight and level. The cooler not being installed properly shouldn’t stop the computer from turning on, but it can be a sign that there’s something wrong with the CPU.

Intel CPU’s will only go in one way, because they have a pair of notches that fit with the socket. AMD CPU’s have a gold triangle on one corner of the chip instead, which lines up with the triangle on the socket.

If a processor isn’t installed properly, it can result in bent pins, damaged cooler and even damage to the motherboard. Check for any damage like this when you’re checking out the processor.

cpu cooler




One of the things you need to make sure of is that the memory and the motherboard are compatible. You probably did all the research when buying the parts, but it could be worth double checking.

If the memory is compatible, the next thing to check is that it’s been installed properly. It has to be in the proper place, facing the right direction and fully seated in the slot. The tabs on either side of the slot should click into place and grab the notches at either end of the RAM. If the notch isn’t in place, the RAM isn’t installed properly.





Graphics card

Not every system has a dedicated graphics card, but if yours does, there’s an easy way to find out if it’s the troublemaker. You’ll need to shut the computer down and take the graphics card out, then plug the monitor cable into the motherboard instead. Turn the power supply back on and try booting. If it works, try uninstalling the graphics driver and then download the latest version and install that. When it’s done, reinstall the graphics card and test it. If it still doesn’t work, it’s probably a hardware issue and you’ll want to get in touch with the manufacturer.


graphics card



Boot issues


Nothing happens at all

The first thing to try might sound silly but it’s worth checking. Is the power supply plugged in? Is it connected to the mains? Is the switch on the back of the computer turned on? Ok, just checking!

Next, make sure that the cables running from the buttons on the case are connected properly. The location and layout of the pins can vary, but it should be a two-wide row of pins with a plastic case around it. The cables will be labelled and some of them have positive and negative contacts. Make sure they’re plugged in properly to the right pins. If it still doesn’t work, you might have a problem with the power supply. The only way to check this is to replace it with one you know works.


It starts to boot but fails

If the computer starts to turn on but fails before it reaches the operating system screen, you’ll want to check the connections to the hard drive. Whether it’s an SSD or an HDD, it’ll have two connections: one for power and one for data. Make sure that both of them are connected properly.

If you see the operating system logo before things fail, then it’s more likely to be a problem with the OS installation. Depending on what operating system you use, you’ll need to find out how to get it re-installed, or run a diagnostic check to figure out what’s going wrong.


Hopefully you've managed to sort out the problem. If not, and you need more help, contact Team Knowhow Experts.

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