[Custom PC] How to Prioritize Choosing PC Parts: Start with CPU and GPU

When building a custom PC, choosing the right parts is very important, but many people may wonder which parts to select first and in what order.

Even if the order of selection is wrong, as long as the parts are not purchased yet, there is no problem in starting over and choosing again from scratch.

However, if parts are chosen in a random order, it often becomes difficult to match performance, budget, and compatibility, and there may be more adjustments needed.

Based on experience from building many custom PCs, this article explains a recommended order of priority for selecting PC parts.

This is just one example, and it is not absolutely necessary to follow this order. Please use it as a base and feel free to adjust it according to your own preferences.

Key Points of This Article

Prioritize the four parts that determine basic performance (CPU, GPU, memory, storage).
Among them, choosing the CPU and GPU first makes it easier to balance performance and budget.
Once the CPU and GPU are decided, it becomes easier to narrow down options for the motherboard and power supply unit.

This article also explains how to choose other parts from the perspective of basic knowledge, roles, performance, and compatibility, so please use it as a reference.

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About the Priority Order When Choosing PC Parts

When assembling a computer, there are important parts that determine its basic performance.

Especially, expensive parts like the CPU and GPU have a big impact on performance, so it is important to choose them first.

Also, once the main parts are decided, it is possible to narrow down other parts based on compatibility, making the selection process smoother.

About the Priority Order When Choosing PC Parts

Prioritize the Four Parts That Determine Basic Performance
Among Them, CPU and GPU Are the Top Priority for Performance and Price
The Remaining Parts Can Be Narrowed Down by Specifications

Prioritize the Four Parts That Determine Basic Performance

The main parts that determine the basic performance of a computer are the CPU, GPU, memory, and storage.

Building and assembling a custom PC can be fun, but it is important not to forget that the main purpose of a computer is to process tasks.

Therefore, it is important to have enough performance for the intended use, so the four main parts should be chosen first.

Among Them, CPU and GPU Are the Top Priority for Performance and Price

Among the four main parts, the CPU and GPU, which directly affect processing performance and speed, should be prioritized.

Basically, it is best to decide on the main parts first, so it is important to choose the most important and expensive parts (about 40-60% of the total cost) that directly affect processing performance.

For example, when packing a bag, putting in the large items first makes it easier to fit the smaller items in the gaps, allowing for smooth packing.

On the other hand, if small items are packed first, it is often necessary to take them out and adjust when trying to fit in larger items.

The same applies to choosing parts for a custom PC. By prioritizing the CPU and GPU, which are the main factors for processing performance and cost, the selection process becomes smoother.

The Remaining Parts Can Be Narrowed Down by Specifications

Once the four main parts—CPU, GPU, memory, and storage—are decided, other parts can be narrowed down based on compatibility and specifications.

Therefore, the remaining parts can be decided in succession.

Once the CPU is chosen, the socket type can help decide the CPU cooler.

For the motherboard, it can be narrowed down by whether it supports Intel or AMD, the memory type, and the number of M.2 SSD slots.

Once the CPU and graphics card are decided, the required power can be estimated, making it easier to choose the power supply unit by wattage.

Once the height of the CPU cooler, the length of the graphics card, the depth of the power supply unit, the motherboard type, and the storage configuration are decided, the PC case can also be chosen.

In this way, by deciding on the CPU, graphics card, memory, and storage, which directly affect basic performance, other parts can be narrowed down based on compatibility, making the selection process smoother.

Specific Example of Priority Order When Choosing PC Parts

This section explains the priority order for choosing PC parts in more detail.

Specific Example of Priority Order When Choosing PC Parts

Priority 1: CPU and GPU
Priority 2: Memory and Storage
Priority 3: Motherboard
Priority 4: Power Supply Unit
Priority 5: CPU Cooler
Priority 6: PC Case
Priority 7: PC Case Fan

This is the order often used, but after the fourth item, the order may change depending on the concept of the custom PC.

Therefore, this priority order can be used as a base, but it is not necessary to follow it strictly. Please adjust as needed.

Priority 1: CPU and GPU

PC Parts Priority 1 CPU

PC Parts Priority 2 Graphics Card

The CPU is the part responsible for all calculations in the computer, and the GPU (graphics card) is responsible for graphics processing.

These are important parts that directly affect processing speed and graphics performance (image processing performance), so it is necessary to choose the right performance for the intended use to ensure comfortable operation.

Both are directly related to the computer’s processing performance and account for about 40-60% of the total cost.

By deciding on the main parts in terms of performance and cost, the rest of the parts can be chosen more smoothly.

A graphics card is not always required, but for uses such as 3D games or 3D graphics, it is essential.

On the other hand, for everyday use such as web browsing or watching videos, or for business use focused on office software and email, the graphics performance of the CPU’s built-in GPU is usually sufficient, so a graphics card is not necessary.

If the CPU and graphics card are chosen later, it may be necessary to review the motherboard, CPU cooler, PC case, etc., depending on the configuration, which is not efficient.

For example, changing the CPU manufacturer requires changing the motherboard, and increasing the CPU’s performance may require a better CPU cooler.

If the CPU cooler is changed, it is necessary to check if it fits in the PC case, and if not, the case may also need to be changed.

The graphics card must also fit within the length supported by the PC case.

Priority 2: Memory and Storage

PC Parts Priority 3 Memory

PC Parts Priority 4 Storage

Memory and storage are not as expensive as the CPU and GPU, but they are among the four parts that determine the basic performance of a computer, so their priority is high.

Memory is used to temporarily store data while the computer is working. The larger the memory, the more tasks and applications can be run at the same time.

Also, storage (SSD/HDD) is used to store data long-term, such as files, images, videos, and games.

If the memory is too small, it will be necessary to close applications or wait for the system to manage memory, which is not comfortable.

If the storage capacity is small, less data can be saved, and if the speed is slow, the computer, applications, and games will take longer to load.

In this way, memory and storage are important parts that greatly affect the smoothness and comfort of all tasks, so their priority is high.

Priority 3: Motherboard

The motherboard is the base part that connects all other parts.

The CPU and CPU cooler socket type, memory type and number of slots, and M.2 slot size all need to be compatible with other parts.

Therefore, after deciding on the four parts that determine basic performance, it is a good time to choose the motherboard.

If the priority is lowered further, more compatibility issues need to be considered, making it harder to choose and possibly requiring other parts to be reselected.

In other words, while narrowing down the main parts, it is smoother to choose other parts that are compatible with the motherboard to avoid trouble later.

By deciding on the four main parts, the motherboard can be narrowed down by the following points:

Motherboard for Intel or AMD
Memory type (DDR5, DDR4)
Number of memory slots
Number of M.2 storage slots

It is a good idea to search for a motherboard based on these conditions.

Priority 4: Power Supply Unit

The power supply unit supplies power to other parts, and its main feature is its power capacity.

If the power supply cannot provide enough power for the parts, the computer may become unstable or may not start at all.

The CPU and GPU account for about 60-80% of the total power consumption, so once these two are decided, the power supply unit can be chosen.

Depending on the CPU and GPU, the CPU uses about 60-250W, and the GPU uses about 100-450W.

For reference, memory uses about 5W per stick, the motherboard 30W, NVMe SSD 25W, SATA SSD 3W, HDD 24W, and fans about 3W each.

Since the power consumption of parts other than the CPU and GPU is not always listed in the specifications, use these as rough estimates when calculating power supply capacity.

The number of storage devices and case fans may change the total a little, but in most modern builds, the power used by other PC parts is very small compared to the CPU and GPU.

Therefore, once the CPU and GPU are decided, the power supply capacity can be narrowed down.

Also, if the GPU and storage are decided, the power supply unit can be narrowed down by the required connectors, making it easier to choose.

In addition, consider features such as 80 PLUS certification, modular cables, and fan stop functions for noise and power saving. These will help finalize the choice of power supply unit.

Power supply capacity can also be calculated using the Custom PC Parts Estimate and Compatibility Check Tool.

By simply selecting parts, the tool will automatically calculate the required power, which is very useful.

Priority 5: CPU Cooler

The CPU cooler is a part that cools the CPU, which gets very hot.

Its priority is a bit lower, but it plays an important role in maximizing CPU performance and maintaining stable operation during long use.

From a compatibility perspective, once the CPU and motherboard socket type are decided, the CPU cooler can be narrowed down.

For air coolers, the height must fit in the PC case, and for water coolers, the radiator must fit in the case.

Therefore, by deciding on the CPU cooler before the PC case, it becomes easier to narrow down the case options.

Priority 6: PC Case

The PC case is the part that houses and physically protects other parts.

It greatly affects the overall design of the computer, and one of the joys of building a custom PC is being able to choose from a wide variety of cases, unlike pre-built PCs.

However, if the chosen case cannot fit the other parts or is not compatible, it defeats the purpose.

From a compatibility perspective, since the case houses all other parts, there are many points to check, just like with the motherboard.

For example, check the motherboard type, power supply unit type and depth, graphics card length, CPU cooler height or radiator size, and other compatibility factors.

Therefore, it is easier to choose a PC case after deciding on the other parts, as this allows for more options to be narrowed down.

However, if there is a strong preference for the design of the PC case and it has already been decided, it may be more difficult to choose parts based on this priority order.

Since the PC case has many compatibility requirements, the desired case may be excluded due to compatibility issues. In this case, it is better to choose the case first and then select other parts to match it.

Priority 7: PC Case Fan

The PC case fan is a fan installed in the PC case to improve cooling performance.

Consider the fan size and number that can be installed in the case, the included fans, and, for water coolers, the radiator size when deciding whether to purchase additional case fans.

Therefore, it is easier to choose after deciding on the PC case and CPU cooler.

Since most cases come with included fans, a minimum level of airflow is ensured. Based on this, decide whether to add more fans if higher cooling performance is needed.

Summary: CPU and GPU Are the Top Priority. Deciding on the Main Parts First Makes Everything Smoother!

This article explained the priority order for choosing PC parts.

Here is a summary of the key points:

Key Points of This Article

Prioritize the four parts that determine basic performance (CPU, GPU, memory, storage).
Among them, choosing the CPU and GPU first makes it easier to balance performance and budget.
Once the CPU and GPU are decided, it becomes easier to narrow down options for the motherboard and power supply unit.

First, prioritize the four parts that determine the basic performance of the computer (CPU / GPU / memory / storage).

Also, when making decisions, it is better to start with the main parts, so the CPU and GPU, which are important for processing performance and account for a large part of the total cost, should be the top priority.

Once these four are decided, the remaining PC parts can be narrowed down by compatibility, making them easier to choose.

It is not necessary to always follow this priority order, so please use it as a base and adjust according to the situation.

This article also explains how to choose other parts from the perspective of basic knowledge, roles, performance, and compatibility, so please use it as a reference.