How to Choose Expansion Cards for a Custom PC: Types and Compatibility

Expansion cards are parts used to enhance the performance and functions of a computer, such as graphics cards, Wi-Fi, and Bluetooth.

There are many types of expansion cards, and they can add new features or improve performance to make a computer more convenient, depending on the user’s needs.

Expansion cards are used by inserting them into a PCI Express slot, but it is important to consider the number of lanes and how many slots the card will occupy. This article will explain the different types of expansion cards and how to choose them.

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What is the Role of Expansion Cards?

The role of expansion cards is to expand the performance and functions of a computer.

Later, the types of cards will be explained, but here are some examples:

• Graphics cards to improve graphic performance
• Cards to add Wi-Fi and Bluetooth functions to desktop computers
• Sound cards for higher quality audio output
• Cards to add RAID functions
• Cards to increase the number of USB ports

In this way, expansion cards are used to improve performance or add necessary functions and ports according to the intended use.

Types of Expansion Cards

First, let’s look at the different types of expansion cards.

Wi-Fi/Bluetooth Card [Highly Recommended]

A Wi-Fi/Bluetooth card is an expansion card that adds wireless network communication functions.

With Wi-Fi, a computer can connect to the internet wirelessly, and with Bluetooth, devices like a mouse, keyboard, or earphones can be used wirelessly.

Most of these expansion cards support both Wi-Fi and Bluetooth with a single card.

For laptops, Wi-Fi and Bluetooth are usually standard features, but for desktop computers (especially custom-built PCs), wired connections are standard, so those who want a wireless environment will find this card essential.

With wired LAN, a LAN cable must be run from the router to the computer, which can be surprisingly troublesome.

Especially if the router and computer are in different rooms or on different floors, the cable must be routed along walls or stairs to avoid being noticeable or causing someone to trip.

This can take more time and effort than expected.

Also, by adding Bluetooth, devices like a mouse, keyboard, or earphones can be used wirelessly, making the desk area much tidier.

For uses that require high internet speed and stability, such as online gaming or streaming, a wired LAN may be better.

However, for everyday use or other purposes where wireless is sufficient, simply adding this card can save the trouble of setting up cables.

Sound Card

A sound card is an expansion card that adds audio output functions or improves sound quality for a computer.

Most computers have basic sound functions built in, but using a sound card allows for higher quality music, movies, and game audio.

This is especially suitable for those who care about sound quality or do music production.

By adding a sound card, users can enjoy clear sound from speakers or headphones, or record clearer audio with a microphone.

When choosing a sound card, the performance of the DAC and the types of connection terminals are important.

First, if better sound quality is desired, the performance of the DAC (Digital-to-Analog Converter) is important.

Sound cards with high-quality DACs provide clearer and richer sound.

It is also important to check if the card has terminals compatible with the audio devices to be used, such as headphones, speakers, or microphones.

Checking for surround sound support is also a good idea.

For those who want immersive experiences in movies or games, sound cards that support surround sound such as 5.1ch or 7.1ch are suitable.

Ethernet Card

An Ethernet card is an expansion card that adds a wired network connection (LAN port) to a computer.

With this card, a computer can be connected to a router or modem with a LAN cable for a stable internet connection.

However, most computers already have a LAN port on the motherboard, so for general use, an Ethernet card is not necessary.

Motherboard LAN ports usually support speeds of 1Gbps or 2.5Gbps, but expansion cards can support up to 10Gbps.

However, internet speed also depends on the contract with the provider and the speed of the router, so simply installing this expansion card does not guarantee 10Gbps speeds.

For home internet, 1Gbps is usually enough, but in companies or high-performance network environments, speeds of 10Gbps or more may be required, so consider installing as needed.

Capture Board

A capture board is an expansion card needed for game streaming or live broadcasting.

With this card, it is possible to record or stream high-quality video from a computer or game console in real time.

When choosing a capture card, check the supported resolution and frame rate.

Cards that support high resolution and high frame rates provide smoother and clearer video.

There are USB-connected types that are easy to use and expansion card types that are installed inside the computer.

Expansion card types use PCI Express connections and are usually faster than USB connections, offering better data transfer speed, lower latency, and higher stability.

USB Port Expansion Card

A USB port expansion card is an expansion card that adds USB ports to a computer.

It is useful when there are not enough USB ports on the back or front of the computer, or when high-speed USB standards are needed.

There are expansion cards that support various standards such as USB 2.0, USB 3.x, and USB-C.

Most computers already have enough USB 2.0 and USB 3.x ports.

However, USB-C ports are often missing or there is only one, so adding more can be valuable.

M.2/SATA Connector Expansion Card

An M.2/SATA connector expansion card is an expansion card that increases the number of storage devices that can be installed in a computer.

It is especially useful when there are not enough M.2 slots or SATA ports.

M.2 expansion cards are used to add NVMe SSDs, which are the latest high-speed storage devices, and are known for very fast data transfer speeds.

On the other hand, SATA expansion cards are used to add traditional SATA SSDs or HDDs and are cost-effective.

RAID Card

A RAID card is an expansion card that manages multiple SSDs or HDDs together and uses RAID (Redundant Array of Independent Disks) technology to improve data speed and redundancy.

By distributing data across multiple storage devices, read and write speeds are improved.

Redundancy means having multiple copies of the same data or functions to increase system reliability and availability.

In other words, even if one storage device fails, another with the same data exists, so data loss does not occur.

There are several types of RAID, including striping for speed and mirroring for redundancy, as well as combinations of these.

RAID 1 mirroring is often used to protect important data, while RAID 0 striping is less common.

There are also other combinations, so choose the right one according to the intended use or purpose.

Also, the types of RAID supported vary depending on the RAID card.

For example, entry-level cards may only support RAID 0 and RAID 1, while high-end cards support RAID 5 and RAID 6 as well.

TV Tuner Card

A TV tuner card is an expansion card that allows a computer to receive TV broadcasts.

With this card, terrestrial digital broadcasts and BS/CS broadcasts can be enjoyed on a computer.

When choosing a TV tuner card, first check the supported broadcast formats.

Some cards support only terrestrial digital broadcasts, while others also support BS/CS broadcasts.

How to Choose Expansion Cards [Compatibility]

This section explains how to choose expansion cards with a focus on compatibility.

If an incompatible expansion card is chosen, it may not physically fit and cannot be installed, so always check compatibility.

Let’s explain these points in detail.

Number of PCI Express Slot Lanes

When choosing an expansion card, check if there is an available PCI Express slot of the appropriate size.

PCI Express (PCIe) slots come in different sizes, such as x1, x4, x8, and x16.

For example, x1 slots are short and suitable for low-speed devices, while x16 slots are longer and suitable for high-speed devices like graphics cards.

Therefore, it is important to check which sizes of PCI Express slots are available on the motherboard and choose a card that matches the slot.

Most expansion cards other than graphics cards use x1 slots, so they are generally compatible.

Also, PCI Express slots are backward compatible, so a small x1 expansion card can be inserted into a larger x8 or x16 slot on the motherboard.

With this in mind, check the size and available slots when choosing an expansion card.

Number of PCI Express Slots Occupied [Especially Important for Graphics Cards]

Depending on the number of slots occupied by an expansion card (mainly graphics cards), not all PCI Express slots on the motherboard can be used.

For example, recent high-performance graphics cards commonly occupy 2 slots, and some occupy 2.5 or even 3 slots.

If multiple slots are occupied, the PCI Express slot below the graphics card cannot be used for another expansion card because it overlaps with the graphics card.

Therefore, if you want to install more expansion cards in addition to large parts that occupy many slots, check if there are enough available slots.

Most expansion cards other than graphics cards occupy only one slot, so in that case, all PCI Express slots on the motherboard can usually be used.

If a graphics card is installed, be sure to check for available slots considering the number of slots occupied.

Summary: Wi-Fi/Bluetooth Cards Are Highly Recommended!

This article explained the types of expansion cards and how to choose them based on compatibility.

Here is a summary of the key points:

Expansion cards are often needed for specific uses or purposes, but among them, Wi-Fi/Bluetooth cards are something that almost anyone can benefit from installing.

There is no need for troublesome wired LAN cable setup, and cables for the mouse and keyboard can also be eliminated, making the desk area much tidier.

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