What Is a 105°C Capacitor in Power Supply Units? [High Durability/Stability]

In power supply units, 105°C capacitors are important components that deliver stable performance even in high-temperature environments.

Compared to standard 85°C capacitors, they are more durable and have a longer lifespan, which increases reliability especially in high-load PCs used for 3D gaming, creative work, and servers.

If a PC is used for high-load tasks such as gaming or video editing (which require high power consumption), it is recommended to choose a power supply unit equipped with 105°C capacitors to extend its lifespan and ensure stable power delivery.

This article also explains the basics of power supply standards, cables, and how to choose a power supply from the perspective of performance and compatibility.

≫ Related article: How to Choose a Power Supply for a Custom PC [Performance / Features / Compatibility]

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About 105°C Capacitors in Power Supply Units

This section explains the basic features of 105°C capacitors used in power supply units and how they differ from standard capacitors.

What is a Capacitor?

A capacitor is an electronic component that stores and releases electricity, and is also called a “storage battery” in Japanese.

Capacitors are widely used in electronic and power circuits, and have the following roles:

• Voltage Stabilization
  Suppresses voltage fluctuations during power supply and delivers stable power to the PC.
• Noise Removal (Ripple Reduction)
  Reduces noise (ripple) in the power output and supplies stable DC current.
• Temporary Power Supply (Buffer)
  Provides temporary power during sudden load changes, improving system stability.
• Affects Power Supply Lifespan
  If degraded, can cause voltage fluctuations or failures, shortening the overall lifespan of the power supply unit.

Capacitors are one of the key factors that determine the quality of a power supply unit, greatly affecting its stability and lifespan.

What is a 105°C Capacitor?

A 105°C capacitor refers to a type of capacitor used in power supply units that can withstand high-temperature environments.

Standard capacitors typically withstand temperatures up to 85°C, but as the name suggests, 105°C capacitors can withstand temperatures up to 105°C.

This allows the power supply unit to operate stably even in high-temperature environments.

Especially in devices such as PCs for 3D gaming, creative work, and servers, where internal heat can be high, 105°C capacitors are important for improving reliability.

In addition, 105°C capacitors often have a long lifespan, which helps extend the overall lifespan of the power supply unit.

Comparison of 105°C and 85°C Capacitors

Let’s compare the features of standard 85°C capacitors and high-durability 105°C capacitors.

105°C capacitors can suppress electrolyte evaporation in high-temperature environments, preventing capacity loss and maintaining stable performance over long periods.

On the other hand, 85°C capacitors are cost-effective, but their performance tends to decline and lifespan shortens as temperatures rise.

Therefore, it is important to select the appropriate capacitor based on the usage environment and required reliability of the power supply unit.

Although 105°C capacitors are more expensive as individual components, the price difference in custom PC power supplies is not that significant.

Price differences are more influenced by power capacity, 80 PLUS certification, and cable types and numbers than by which capacitor is used, so there is no need to worry too much about it.

Advantages of 105°C Capacitors

The advantages of 105°C capacitors are as follows.

High Durability

While general electrolytic capacitors often support up to 85°C, 105°C capacitors operate stably even in high-temperature environments up to 105°C.

Especially in high-load applications such as gaming, creative work, AI learning, and workstations, power consumption is high and the temperature inside the power supply unit tends to rise.

Therefore, heat resistance of capacitors becomes important.

As temperature increases, capacitors degrade more quickly, so using 105°C capacitors that can withstand high temperatures extends lifespan and improves the overall reliability of the power supply unit.

Longer Lifespan

Over long-term use, internal electronic components degrade, eventually leading to the end of the power supply unit’s lifespan.

Among these, electrolytic capacitors are particularly susceptible, and their lifespan is closely related to that of the power supply unit.

The lifespan of electrolytic capacitors is halved for every 10°C increase in temperature (Arrhenius Law).

The Arrhenius Law is a general standard for predicting the degradation of electrolytic capacitors.

Based on this standard, the estimated lifespan at different operating temperatures is as follows:

For example, if an 85°C capacitor is used at 85°C, its lifespan is 2,000 hours, while a 105°C capacitor used at the same temperature has a lifespan of about 8,000 hours.

In actual use, the internal temperature of a power supply unit is usually around 50–70°C, so power supplies with 105°C capacitors may have several times the lifespan of those with 85°C capacitors.

Stable Power Supply

For each PC part to work properly, it is necessary to supply stable power with minimal voltage and current fluctuations.

Especially during high loads or long-term use, unstable power can cause the PC to malfunction or, in the worst case, damage components.

The higher the quality of the capacitor, the less fluctuation in output voltage, and the lower the noise and ripple (fine voltage fluctuations), leading to stable operation of the entire PC.

In particular, PC power supplies need to provide large amounts of power instantly when the CPU or GPU is under heavy load.

Even during such sudden power fluctuations, 105°C capacitors are less likely to lose capacity and can maintain stable voltage.

Reduced Risk of Leakage and Swelling

Using 105°C capacitors reduces the risk of electrolyte leakage and swelling.

Their resistance to high temperatures makes it harder for the internal electrolyte to evaporate, resulting in less risk of leakage or swelling.

This helps reduce the risk of failure for the entire power supply unit and allows stable operation over long periods.

Disadvantages of 105°C Capacitors

The disadvantages of 105°C capacitors are as follows.

Higher Cost

As individual components, 105°C capacitors are more expensive than standard 85°C capacitors.

Because 105°C capacitors must operate stably in high-temperature environments, they require higher-quality materials and manufacturing processes, resulting in higher production costs.

However, when looking at the price of power supply units, the price difference between those with 105°C and 85°C capacitors is not that large.

Rather, price differences are more influenced by power capacity, 80 PLUS certification, and other specifications.

Few Advantages in Low-Temperature Environments

In low-load environments, the burden on the power supply unit is small, so even if a high-quality power supply with 105°C capacitors is chosen, its advantages may not be fully utilized.

A low-load environment refers to a state where the PC’s power consumption is low and the load on the power supply unit is small.

For example, the following uses are considered low-load environments:

• Office PCs or business PCs (document creation, email checking, etc.)
• Light tasks such as watching videos or browsing social media
• Idle state (when no tasks are being performed)
• Power-saving PCs (small PCs, PCs with low-power CPUs)

In these cases, the load on the power supply unit is small, so internal temperature rise is minimal and capacitor degradation is slow.

Although 105°C capacitors have high durability in high-temperature environments, in low-load environments, the power supply does not generate much heat, so their heat resistance is not fully utilized.

For example, in high-load gaming PCs, the internal temperature of the power supply can reach 70–80°C, but in low-load office PCs, it often stabilizes at around 40–50°C.

At these temperatures, 85°C capacitors can provide sufficient lifespan, so there is less need to choose 105°C capacitors.

Features of Power Supplies with 105°C Capacitors

This section explains the features of power supply units equipped with 105°C capacitors.

105°C Capacitor Models Exist Even in Standard Power Supplies

Since 105°C capacitors are more expensive than standard 85°C capacitors, it may seem that only high-end power supplies use them.

However, even entry-level and mid-range power supplies often have models equipped with 105°C capacitors.

In fact, about 50–60% of power supplies use 105°C capacitors, so there are plenty of products to choose from that meet other desired features and specifications.

Therefore, for high-load use, it may be a good idea to narrow down the options to power supplies with 105°C capacitors.

For High-Load Applications Such as Gaming, Creative Work, and Workstations

Power supplies with 105°C capacitors minimize output voltage fluctuations and reduce noise and ripple, enabling stable operation even in high-load situations.

105°C capacitors are also better at maintaining stable voltage during sudden power fluctuations, making them recommended for applications where the CPU or GPU is often under heavy load.

High-load applications refer to uses where the CPU or GPU, which consume most of the power in a custom PC, are heavily loaded.

• 3D gaming
• Image and video editing
• 3D rendering
• AI learning
• Data analysis
• Simulation calculations
• Workstations

According to the Arrhenius Law, in environments where the internal temperature of the power supply unit tends to be high, 105°C capacitors are more durable and reliable than 85°C capacitors with lower heat resistance.

Often Use Japanese-Made Capacitors

Power supplies with 105°C capacitors often use Japanese-made capacitors.

After checking several power supplies, most used Japanese 105°C capacitors, with some rare cases using Taiwanese ones.

The reason for choosing Japanese manufacturers is their high quality and reliability.

Especially for 105°C capacitors, which are crucial for power supplies required to operate in high-temperature environments.

Japanese manufacturers offer capacitors with excellent performance thanks to years of technological development and quality control.

This improves the durability and stability of the power supply unit, allowing for safe use over long periods.

In addition, Japanese capacitors meet strict quality standards, contributing to the overall reliability of the product.

How to Identify Power Supplies with 105°C Capacitors

This section introduces how to check if a power supply unit is equipped with 105°C capacitors.

Check the Power Supply Specifications

To see if a power supply uses 105°C capacitors, check the product specifications on the official page.

Usually, this information is written in the feature list at the top of the page or in the section explaining each feature.

Some products also have a separate PDF datasheet where this is mentioned.

On the other hand, it is often not written in specification tables, so be careful when checking specifications.

Using “Ctrl + F” to search the page for “105” or “105°C” can help you find the information quickly.

Search with Custom PC Tools

The Custom PC Parts Estimate & Compatibility Check Tool allows you to filter power supplies that support 105°C capacitors, so be sure to use it.

Also, since each power supply has a link to its product page, you can check the detailed specifications directly without searching for the product name, which is convenient.

Summary: For Long Lifespan, Stability, and High-Load Use, Power Supplies with 105°C Capacitors are Recommended!

This article explained the advantages and disadvantages of 105°C capacitors in power supply units, the features of power supplies with 105°C capacitors, and how to identify them.

Here is a summary of the key points:

For low-load uses such as web browsing, document creation, or email, the power supply unit does not get very hot, so the advantages of 105°C capacitors may not be noticeable.

Of course, it is fine to choose them for their long lifespan, but to maximize their benefits, they are best suited for high-load applications such as 3D gaming, video editing, or AI learning where the CPU or GPU is heavily used.

In terms of price, there is not much difference between power supplies with 105°C and 85°C capacitors. In fact, price differences are more influenced by power capacity, 80 PLUS certification, and cable types and numbers.

Also, it is not just a small number of power supplies that support 105°C capacitors—about 50–60% do, so there are plenty of options.

Therefore, for users who use their PC for high-load tasks, it may be a good idea to narrow down the options to power supplies with 105°C capacitors.

This article also explains the basics of power supply standards, cables, and how to choose a power supply from the perspective of performance and compatibility.

≫ Related article: How to Choose a Power Supply for a Custom PC [Performance / Features / Compatibility]

あわせて読みたい

PC Parts Estimation & Compatibility Check Tool

Automatically checks each component you need when selecting parts for a custom-built PC—perfect for beginners.