From selecting components to putting them together like Legos, it is always fun to build a PC. However, you need to avoid a few PC building mistakes to prevent components from getting damaged. For instance, you need to ground yourself so as not to short anything.

Similarly, it is always useful to estimate how long the entire building process is going to take. So you won’t have to rush anything in the end.

If it’s your first time building a PC, then you have probably read a bunch of guides telling you how to build it. Well, while these guides are quite helpful in telling you what to do, they don’t tell you what NOT to do.

Hence, many first-time builders end up making a bunch of mistakes, which can cost a ton of time and money. To help you avoid them, we have compiled a list of the most common PC-building mistakes that beginners are likely to make.

Let’s dive right in!

Key Takeaways

  • Always buy a reliable PSU that provides the required wattage. Also, you should make sure the components you’re purchasing are compatible.
  • Assemble the PC on a large and suitable surface. Place the IO shield and the standoff screws in the casing first.
  • Make sure you’re installing the CPU correctly. Apply the right amount of thermal paste and remove the plastic cover on the heatsink. Also, always install the RAMs in the right DIMM slots correctly.
  • Install the fans in the right orientation to provide good airflow. Make sure you have plugged everything in. Always plug in the display to the GPU and not the motherboard.
  • Once your PC is up and running, remember to monitor the temperatures to look for abnormalities. Also, it is best to hold on your component’s boxes and warranty cards.

PC Building Mistakes To Avoid

Following are some mistakes you must avoid while building your PC.

Cheaping Out On The Power Supply

When building a budget PC, it is possible for you to cut costs here and there. But you must never go for a low-quality PSU to save a few bucks.

By saying “Never cheap out on the power supply”, we don’t mean that you should buy the highest-end PSU available on the market; we mean that you should go for an affordable PSU from a reliable brand that can provide adequate power for your components. 

Before purchasing a PSU, it is always best to estimate how much power your PC is going to need, and then you can select a PSU that can provide a little over that required power.

Many power supply calculators are available online, like CoolerMaster and OuterVision. You can rely on these calculators to estimate how much wattage the PSU you’re looking for should provide.

Buying Incompatible Components

Another rookie mistake that a first-time PC builder is likely to make is buying incompatible components. For instance, you should not buy DDR3 RAMs with a motherboard that supports DDR4, because that would be incompatible.

Similarly, pairing an Intel Core i5-10600K processor with an LGA1151 socket motherboard will also not work because the 10th generation Intel chipsets uses the LGA1200 socket. 

To avoid such issues, it’s best to build a virtual PC with your components on sites like PCPartPicker because it will tell you whether the selected components are compatible or not.

Another thing to look out for is to make sure that your selected PC parts don’t bottleneck. A bottleneck happens when there is a huge performance difference between your components. Hence the higher-powered component won’t work to its fullest.

For instance, if you pair a 3080Ti with an i5-3470 processor, the GPU will not perform to its full potential because there is a bottleneck. You can use an online bottleneck calculator to look out for bottleneck issues.

Not Building On A Suitable Surface

Once you have got everything together, a common mistake you might make is assembling your PC on a small, uneven, or overall unsuitable surface.

Look, even though building a PC is not rocket science, and you can probably do it with a little bit of online help, there are still a lot of screws and cables involved throughout the process. So, if you don’t want to lose anything, then it’s best to keep everything organized on a large and clear surface.

Pc Building Mistakes
Pc Building In Progress – Image Taken By Tech4Gamers.

You should never put any component on a metal or conductive surface when assembling your PC. Because once powered on, the metal surface can fry the electronics. Additionally, it is best to build your PC or at least place your motherboard on an anti-static foam. Otherwise, simply wearing an anti-static wristband can also be a safer choice.

Forgetting The IO Shield

Forgetting the IO shield is one of the most common PC building mistakes. You will find an IO shield in your motherboard’s box. This IO shield must be installed BEFORE mounting the motherboard on the PC case. 

An IO shield is an important part of your PC; it prevents the motherboard from collecting dust and protects it against EMI and static discharge. When building a PC, it is very common to forget the IO shield, and by the time you might realize its absence, the motherboard might already be mounted on the case.

PC Building Mistakes
Everything you need to know about an IO Shield – Image: Tech4Gamers

Once the motherboard is mounted, there might not be enough room to install the IO shield, so you will have to remove the motherboard again. That’s why it’s best to install the IO shield on the casing as soon as you unbox the motherboard. 

If you don’t know how to install an IO shield, then read our guide on them, where we have covered the steps to install IO shields correctly.

Forgetting The Motherboard Standoff Screws

Another beginner mistake that many builders make is forgetting to install the standoff screws. These standoff screws create a space between the motherboard and the PC casing.

The space is necessary, so your motherboard does not directly touch the case’s metal surface, ensuring it is protected against short circuits and other electrical damage.

Before you start assembling your PC, it’s best to install these standoff screws. You can find them in your PC casing. If you don’t know where to install them, then simply align your motherboard with the casing and screw the standoffs in the case’s holes.

Standoff screws are an important part of your PC build, and forgetting to install them can cause some serious damage to your components.

Incorrectly Installing The CPU

PC Building Mistakes
Computer Processor – Image By Tech4Gamers.

Once you have the case equipped with the IO shield and the standoff screws, it’s time to start installing components to the motherboard.

The first part you’re likely to install is the CPU, and before you do so, it’s best to keep in mind that CPUs and computer parts, in general, are quite fragile. So, you need to keep a gentle hand because any mishandling can cost you a lot.

Many novice PC builders end up incorrectly installing the CPU, which can bend its pins and render it useless. First of all, you should not hold the CPU from its top or bottom; the correct way to hold a CPU is from its sides.

After that, when inserting it in the socket, look for the marking on the chip’s corners. These marks will tell you how to line up the chipset with the socket.

Once the markings on the CPU are aligned with the motherboard’s marking, you can install the CPU. 

Applying Too Much Or Too Little Thermal Paste

Once you have the CPU in place, you will move on to applying thermal paste. Many beginners fear that they might apply too little thermal paste, so they end up applying it too much. Which, in turn, can have an opposite effect where your CPU’s thermals don’t perform as well.

Similarly, applying too little thermal paste is also not good. The lack of thermal paste will cause the heatsink to perform ineffectively, resulting in high temperatures.

As a general rule, you should apply thermal paste equivalent to the size of a grain of rice in the middle of your CPU. After that, the heatsink will spread the thermal paste across the chipset evenly.

Forgetting To Remove The CPU Cooler’s Plastic Cover

Before installing the CPU cooler, you need to remove the plastic cover on the heatsink. Most CPU coolers come with this cover, and it is usually labeled something like “remove before use”. 

Without removing this cover, your CPU cooler will not touch the thermal paste. Hence it will basically not cool anything. On top of that, the plastic cover will soon melt due to the heat from the processor, and having molten plastic on your CPU is never a good thing.

So, it is necessary to remove the CPU cooler’s plastic cover. Also, on the topic of CPU coolers and forgetting things, always remember to connect the cooler’s power cable to the motherboard.

The cable must be wrapped somewhere around the cooler fans, and it should be connected to a port near the CPU socket labeled “CPU FAN” or something similar.

If you cannot find the connector, then refer to the manual that came with the motherboard. 

Incorrectly Installing The RAM

Can You Mix Ram Slots
Four RAMs installed

If it’s your first time building a PC, then you’re highly likely to make this mistake. You might be thinking, how is this difficult? There are 4 RAM slots, and I have two RAMs. I can just insert them in the slots, and the work is done.

Well, first of all, you cannot insert the RAMs into just any slot. You need to go through the motherboard’s manual to see which slots to populate first with dual-channel memory. In most cases, the RAMs should be installed in alternate slots. Similarly, the RAM should be installed in the slot furthest from the CPU socket for a single memory stick.

It is highly recommended that you check the motherboard’s manual for more information about the RAM slots. 

Apart from inserting in the wrong slots, many users also find it difficult to install the RAMs correctly. If you look closely, you will notice that there is a 60/40 split of the pins on the RAM stick. Similarly, there is a 60/40 split on the slot as well. 

So, you need to place the RAM in its slot with the correct alignment and push its two ends with equal pressure. Once the RAM is properly installed, you will hear two clicking sounds. 

Not Installing Case Fans The Right Way

PC Building Mistakes
PC Case Airflow

Many don’t know this, but poor airflow is one of the major PC building mistakes. Having good airflow is integral to your PC’s performance and health. Otherwise, your PC will overheat, causing issues like reducing your motherboard’s lifespan.

If your PC case has pre-installed fans, then you shouldn’t worry about making this mistake. However, if you plan to install your own fans, you should pay attention to how you orient them, as it can make or break your PC’s airflow.

You should remember that hot air rises from the bottom towards the top, while most of the heat-generating components are placed at the back of your casing.

So, as a general rule of thumb, it’s best to install the fans that will suck cool air from the room at the front and the bottom of the PC and install the fans that will blow out the hot air from the PC to the surroundings at the back and the top. 

Forgetting To Plug In Everything

It might sound obvious at first, but many people forget to plug in a cable or two, which can prevent your PC from powering on. This mistake is extremely frustrating because once you have put everything together and something does not seem to work, you will have to trace back which cable did you forget to plug in.

On top of that, if another component hides the connector or the port, then you will have to take it off to fix the mistake. That’s why it is necessary to ensure that every component is correctly plugged in before you wind up your build.

You can create a checklist on paper to list down everything you need to plug in and everything you have already plugged in. For starters, make sure the CPU, the motherboard, and the GPU are plugged in with the power supply. Apart from that, you also need to connect the front I/O panel, the CPU fans, the RGB lighting (if you’re using them), and much more.

Plugging The Display To The Motherboard

Dialog box that says "VGA NO SIGNAL"

You assemble your entire PC, plug everything in, and finally boot it up. You hear your fans spinning, and everything boots up, but, there is no display. This is one of the most common issues that novice PC builders run into, and the solution is quite simple.

It happens because you plug in your monitor to the display port of the motherboard instead of the GPU. So, everything will boot up, but your monitor will show nothing except the “No Signal” box.

Even if your monitor works and it starts displaying, you will notice a significant lack of performance because your PC uses the CPU’s integrated graphics, not the dedicated one.

To avoid this mistake, make sure you plug in the monitor to the display port of the graphics card.

Not Monitoring Temperatures

Many new builders don’t monitor the temperatures once the build is up and running. This mistake can be very costly if something wrong with the PC doesn’t show up immediately.

For instance, your CPU might be running a little too hot because the cooler is not installed properly. So, it’s best to monitor the temperatures after building a PC. You can use software like Speccy, MSI Afterburner, and HWMonitor

Using multiple software to monitor the temperatures is recommended because it is common for them to bug out and show inaccurate readings.

Throwing Away Boxes And Warranty

It is always best to hold on to the warranty cards and the boxes. Everything might work perfectly for now, but you don’t know whether your GPU will run into some issues in the near future. 

Many users make the mistake of throwing away their component’s boxes and warranty. Apart from just the warranty, you should still hold on to the boxes if you plan to resell the components in the future.

Final Words

These were some PC building mistakes that you should avoid. Everybody learns from mistakes, and you’re likely to make a bunch of them if it is your first time building a PC. However, it is best to research as much as possible to avoid any mistakes that might cost you a lot.


Which component should I install first on my motherboard?

It is always best to install the CPU first, after that, apply the thermal paste, then install the cooler, and then move on to installing RAMs. Sometimes, the cooler can make it difficult to install RAMS. So, you might have to install the RAMs first.

How to bring down CPU temperatures?

Start by reapplying the thermal paste. If that doesn’t lower the CPU temperatures, then might have to invest in a good CPU cooler. Also, make sure that your casing fans are placed correctly to provide good airflow.

Was our article helpful? 👨‍💻

Thank you! Please share your positive feedback. 🔋

How could we improve this post? Please Help us. 😔

Ali Rashid Khan is an avid gamer, hardware enthusiast, photographer, and devoted litterateur with a period of experience spanning more than 14 years. Sporting a specialization with regards to the latest tech in flagship phones, gaming laptops, and top-of-the-line PCs, Ali is known for consistently presenting the most detailed objective perspective on all types of gaming products, ranging from the Best Motherboards, CPU Coolers, RAM kits, GPUs, and PSUs amongst numerous other peripherals. When he’s not busy writing, you’ll find Ali meddling with mechanical keyboards, indulging in vehicular racing, or professionally competing worldwide with fellow mind-sport athletes in Scrabble at an international level. Currently speaking, Ali has completed his A-Level GCEs with plans to go into Business Studies, or who knows, perhaps a full-time dedicated technological journalist.