The power supply (PSU) is an important part of a computer system that converts electrical current from a source into a current that hardware can use. Without a good PSU, all computer components, from the processor to the graphics card, will not function optimally. Therefore, choosing the right PSU is very important so all components have enough stable power.
The importance of PSUs in computer systems lies not only in the provision of power but also in the overall performance of the system. Every device in a computer, such as motherboards, hard drives, and graphics cards, has certain power needs that must be met. If the PSU is not able to provide enough power, it can cause various problems, such as degraded system performance, damage to hardware, and system instability that can result in crashes or freezes.
Calculating Power Requirements
One of the important steps in choosing a power supply is to make sure all of your computer’s components are getting enough power. Here is a guide to calculating power requirements.
Device Power Consumption Table
Here are the estimated power consumption of some of the main components of the computer:
| Component | Power Consumption (Watts) |
| Processor | 10–100 W |
| Graphics card (GPU) | 20–300 W |
| Hard drive (HDD/SSD) | 3–15 W |
| CD/DVD drive | 10–25 W |
| Motherboard | 5–50 W |
| RAM | 2–5 W per module |
| CPU Cooler | 5–10 W |
How to Calculate Total Power Required
1. Identify the Components Used
Take note of all the devices on your computer, such as CPU, GPU, RAM, hard drive, and other enhancements.
2. Calculate the Power Consumption of Each Component
Use the power consumption table to estimate the power needs of each component.
3. Total Power Requirements
Add up all the power requirements of the components. Examples:
- Intel Core i5 processor (65 W)
- NVIDIA GeForce GTX 1660 Graphics Card (120 W)
- 1 Hard Drive (10 W)
- 1 SSD (5 W)
- Motherboard (30 W)
- 2 module RAM (2 × 5 W = 10 W)
Total power requirement = 65 + 120 + 10 + 5 + 30 + 10 = 240 W
4. Provide Power Backup
It is recommended to add about 20–30% of the total power as a backup to maintain stability, especially when components are operating at maximum load.
Example:
- Total power requirement = 240 W
- Power reserve = 30% × 240 = 72 W
- Total minimum power power supply = 240 + 72 = 312 W.
Online Tools for Calculating Power
Several online tools can help you calculate your power needs more easily and accurately. Some of them are:
- OuterVision Power Supply Calculator: This tool allows you to insert all components and provide an estimate of the required power.
- Cooler Master Power Supply Calculator: Provides a simple interface for entering hardware specifications and calculating power requirements.
- Newegg Power Supply Calculator: Allows the user to select a component from the list and calculate the total wattage required.
Choosing the Right Power Supply
Choosing the right power supply is essential to ensure the performance and stability of your computer system. Here are some things to keep in mind:
1. Suitable Wattage Capacity
The wattage capacity of the power supply must match the total power requirements of all computer components. Be sure to calculate the total wattage required, including the processor, graphics card, and other devices. As a general guide:
- Use the power requirement calculation (as described earlier) and add 20–30% as a backup.
- Avoid using a power supply with too small a capacity, as it may cause the system to be unstable, or too large, as it will waste electricity.
- Standard computers typically require a power supply with capacities ranging from 400W to 600W.
- A more powerful gaming computer or workstation may require a power supply with a capacity of more than 600W.
2. Energy Efficiency (80 PLUS Certification)
Energy efficiency is very important when choosing a power supply. 80 PLUS certification shows how well the power supply converts AC into DC. There are several levels of certification, namely Bronze, Silver, Gold, Platinum, and Titanium, with Titanium being the most efficient. Using an efficient power supply can lower electricity costs and generate less heat.
Certification levels include:
– 80 PLUS Standard: Efficiency of at least 80%.
– 80 PLUS Bronze: Efficiency 82–85%.
– 80 PLUS Silver: Efficiency 85–88%.
– 80 PLUS Gold: Efficiency 87–90%.
– 80 PLUS Platinum: 90–94% efficiency.
– 80 PLUS Titanium: Efficiency is more than 94%.
3. Maximum Power Rating Sticker and Temperature Effect
Each power supply has a rating sticker that indicates the maximum power that can be produced at a certain temperature, such as 25°C. However, if the temperature increases, for example when the PSU is installed in a poorly ventilated case, the ability to generate power can decrease. Therefore, it is crucial to choose a power supply that can provide maximum power at higher temperatures.
Some manufacturers may list numbers that are too optimistic, so the maximum power often decreases as the temperature inside the case rises. Therefore, choose power supply from trusted manufacturers and provide realistic ratings.
4. Number and Type of Connectors Required
Make sure the power supply has the appropriate number and type of connectors for all your components. Some important connectors include:
- 24-pin ATX connector for motherboard.
- 4-pin or 8-pin CPU connector for processor.
- 6-pin or 8-pin PCIe connector for graphics cards.
- SATA connectors for hard drives and SSDs.
If you have a device that requires a lot of power, make sure your power supply has enough connectors. Check the specifications of your components to ensure that the power supply is capable of meeting the connection needs.
5. Best Brand and Model Recommendations on the Market
Some of the well-known and recommended power supply brands and models in the market include:
- Corsair RM Series: Known for its high efficiency and quality. Offers a wide range of models for users from entry-level to high-end. Example: Corsair RM850x (80 PLUS Gold).
- Seasonic Focus Series: Have high certification and a good reputation in reliability. Example: Seasonic Prime TX-750 (80 PLUS Titanium).
- EVGA SuperNOVA Series: Popular choice with competitive price and long warranty. Example: EVGA SuperNOVA 750 G5 (80 PLUS Gold).
- Cooler Master: Suitable for users on a budget. Example: Cooler Master MWE 650 Bronze V2 (80 PLUS Bronze).
- Be Quiet!: Focus on high efficiency and quiet operation. Example: Be Quiet! Straight Power 11 (80 PLUS Platinum).
- Thermaltake Toughpower Series: Known for its innovative features and modular design.
Size and Compatibility
When choosing a power supply, it is important to pay attention to its physical size so that it can fit well in a computer case. There are several standard sizes to consider, such as ATX, SFX, and others. Be sure to check the specifications of your case to find out the maximum size of power supply that can be used.
- Power Supply ATX: The most common size and fits most desktop cases.
- Power Supply SFX: Smaller and typically used in mini-ITX cases or more compact systems.
Before purchasing, measure the available space in the case to ensure that the new power supply can fit without disturbing other components.
Position of the On/Off Button by the Case
The position of the on/off button on the power supply also needs to be considered. This button is usually located on the back side of the PSU and should be easily accessible after installation. If the button is too close to the wall of the case or is blocked by other wires, it will be difficult to operate it.
Some things to consider:
- Make sure the buttons are easily accessible without having to move the case.
- Some cases may have designs that affect the position of the buttons, so be sure to check for compatibility before purchasing.
How to Replace a Computer’s Power Supply
Replacing power supply computers can be done with regular steps. Here is a complete guide to replacing the power supply safely and efficiently.
1. Preliminary Preparation
- Make sure the computer is completely off and unplug the power cord from the power outlet to avoid the risk of electric shock.
- Take a tool such as a screwdriver (usually a Phillips screwdriver) and an antistatic strap to protect against damage from static electricity.
2. Removing the Old Power Supply
Opening the Computer Case:
- Remove the screws that lock the computer case, usually on the back.
- Carefully open the case, making sure that no wires or other components are pinched.
Carefully Remove the Cable:
- Take notes or take photos of the cable’s position before removing it for easy reattaching.
- Carefully disconnect the cables from the motherboard, graphics card, and storage devices. Use your fingers or tools if necessary, but avoid pulling on the cord roughly.
3. Installing a New Power Supply
Installation of a new power supply:
- Place the new power supply inside the case in the appropriate slot.
- Secure the PSU with the screws provided.
Ensuring All Connectors Are Properly Installed:
- Connect the 24-pin ATX connector to the motherboard.
- Connect the CPU connector (4-pin or 8-pin) to the processor.
- Install the PCIe connector for the graphics card (if required).
- Connect the SATA connectors for the hard drive and SSD.
Make sure all connectors are properly seated and that no wires are pinched when closing the case.
4. Testing After Installation
- Turn on the computer and check that all the components are working properly. Listen to the fan sound and look at the indicator light on the motherboard.
- Use monitoring software to check the output voltage of the PSU and make sure everything is within normal limits.
- Perform load testing by running heavy applications or games to ensure the system remains stable.