A high-quality power supply unit (PSU) is essential for creating a reliable gaming rig that will last. But it's the component that most people don't usually consider when building a computer. Without a good PSU, your build could experience stability problems, or it could even go up in smoke.
A power supply unit needs to provide enough juice for the computer to run.
Using the wrong power supply can not only shorten the lifespan of your components but can also damage them beyond repair. Suppose a power supply can't handle the power load of all the components in your build. In that case, you may experience crashes, freezes, data loss, or component failure. But don't worry! We can prevent this from happening.
In this article, I'll go over the things you should consider when choosing a power supply for your gaming computer.
Check out my Recommended PSUs
below.
What to Look for in a Power Supply
The main job of a power supply is to convert the alternating current (AC) from your wall outlet into the direct current (DC) needed by the components inside your computer.
Power Output
An important factor when buying a PSU is the supported wattage.
You can estimate your power needs by using the following chart.
| Component | Peak Power Usage |
|---|---|
| Top-Tier CPU (e.g. Intel's i9-13900K) | 253 W |
| Mid-Tier CPU (e.g. Intel's i5-13600K) | 181 W |
| Top-Tier Graphics Card (e.g., Nvidia RTX 4090) | 450 W |
| Mid-Tier Graphics Card (e.g., Nvidia RTX 3060) | 170 W |
| Motherboard, RAM and onboard components | 80 W |
| Optical Drive | 30 W |
| 3.5" Hard Drive | 9 W |
| M.2 or 2.5" SSD | 9 W |
| 140 mm Case/CPU Fan | 6 W |
| 120 mm Case/CPU Fan | 6 W |
| 80 mm Case/CPU Fan | 3 W |
By adding up these numbers, you can estimate peak power usage.
With four SSDs, three large case fans and two CPU fans, the top-tier gaming computer example totals 849 W: 253 W for the CPU + 450 W for the GPU + 80 W for the motherboard, RAM and onboard components + 36 W for SSDs + 30 W for fans.
We aim for about 150 W of headroom and keep at least 100 W spare when choosing a common PSU capacity. This leaves room for estimation differences and small additions such as drives or fans. Also meet the graphics card manufacturer's minimum system-PSU recommendation.
In the above top-tier gaming computer example, 849 W + 150 W = 999 W, so a 1000 W power supply would be a reasonable choice.
In most cases, buying a little more wattage than you need is a safer choice for ensuring system stability.
If you overclock, use the higher CPU and GPU power limits when estimating demand, then add the buffer. Check the graphics card manufacturer's PSU recommendation for your exact model as well.
Power Efficiency
For the same power delivered to components, higher-efficiency PSUs draw less electricity from the wall and waste less energy as heat.
The 80 PLUS certification program for power supplies helps to promote energy efficiency by indicating its efficiency rating.
Higher-efficiency power supplies may have a higher upfront cost. However, they can also save you money on electricity in the long run. I've experienced firsthand that utilizing a PSU with a high 80 PLUS efficiency rating can significantly reduce energy usage, heat production, and power costs, depending on your usage patterns.
For most gaming PCs, a good 80 PLUS Gold PSU is a sensible balance of price and efficiency. Start with the wattage recommended above, then check that the model has the connectors you need and a good warranty.
| Certification Level | 10% Load | 20% Load | 50% Load | 100% Load |
|---|---|---|---|---|
| 80 Plus | 80% | 80% | 80% | |
| 80 Plus Bronze | 82% | 85% | 82% | |
| 80 Plus Silver | 85% | 88% | 85% | |
| 80 Plus Gold | 87% | 90% | 87% | |
| 80 Plus Platinum | 90% | 92% | 89% | |
| 80 Plus Titanium | 90% | 92% | 94% | 90% |
Cables
Connectors
Make sure your PSU has the correct connectors to support the hardware in your system. Cheaper PSUs may cut costs on connectors and cables by offering fewer options and shorter lengths.
Check with your motherboard and graphics card documentation to determine which connector types are needed. Buy a popular, recently-released PSU; it will likely have the necessary connectors for a new gaming PC build. However, if you use old components or an old power supply, you may find some incompatibilities.
Here are some common connector types that power supplies support:
- 24-pin connector for the motherboard
- 4/8-pin connector for the CPU
- 6/8/16-pin connectors for graphics cards
- SATA Power connector for each SATA HDD or SDD storage device
The latest graphics cards and ATX 3.0 PSUs support a new 16-pin PCIe 5.0 connector that replaces multiple 8-pin connectors.
Modular Cables
Typical power supplies come with various cables to connect your components. However, extra unused power cables can work against you by interrupting airflow.
In comparison, modular and semi-modular power supplies allow for attaching only the cables you need. As the name implies, semi-modular power supplies have some wires soldered on, while you can optionally connect others.
Cable Lengths
Most power supplies will have cables long enough to support mid-sized towers comfortably. If you have a full-size tower, you may want to check reviews and documentation to ensure that the cables are long enough to allow good cable management. In my experience building computers, I have discovered the inconvenience of power supplies with short cable lengths. Short power cables can pose a massive challenge when reaching the necessary components, making case layouts look cluttered and obstructing airflow.
Power Supply Form Factors
Various form factors are available for power supplies, but most PC gamers will want the standard ATX power supply.
Small form factor PSUs allow for usage in many computer case shapes, including mini-PCs.
Power Supply Features
Overvoltage protection and short circuit protection can save your components in the case of a surge or accident. I've experienced multi-component failures before and would prefer a PSU with these protective features to avoid buying a whole replacement system when the cause is preventable.
LED lighting is another feature you might consider, depending on your gaming PC goals.
Choosing a Cost-Effective Power Supply for Gaming
You may live in a dorm or a family member's house and not pay electricity bills. Or you don't expect to use your computer daily for an extended period. In those cases, the lower upfront cost of a less efficient PSU may be the better choice. I once lived in a dorm without having to pay for electricity. With moderate computer usage, I decided to try a less efficient PSU to save on upfront costs. It helped me in that situation.
On the other hand, if you care more about your electric bill or the environment and plan to maintain higher CPU or GPU usage, a more efficient PSU may be better. As I became more conscious of my electric bill and environmental impact, I observed that my high CPU and GPU usage took a toll. So I researched and analyzed my options. Based on my findings, I invested in a more efficient PSU. It was a decision that paid off, as I saw a noticeable decrease in electricity costs over time.
Choose the wattage recommended for your configuration, and buy extra capacity if you plan a larger GPU upgrade. A higher wattage rating does not mean the PSU constantly draws that much power; your components determine the load. Compare the price, connectors and warranty of suitable models before paying extra for a higher efficiency tier.
I've come to understand the significance of considering my specific circumstances and needs when choosing a PSU. Whether it's about saving costs or reducing my environmental footprint, making an informed decision is beneficial in the long run.
Recommended Power Supplies for Your Gaming PC
Recommended 750-1650 Watt ATX 3.0 PSU
Thermaltake Toughpower GF3 ATX 3.0
Thermaltake Toughpower GF3 ATX 3.0 Power (Watts): 750 to 1650 Efficiency: GOLD 80 PLUS Warranty: 10-year The Thermaltake Toughpower GF3 ATX 3.0 Power Supply on Amazon
is our recommended 750-1650 watt ATX 3.0 PSU.We were impressed when we saw the efficiency rating of the Thermaltake Toughpower GF3 ATX 3.0. Its GOLD 80 PLUS certification indicates that it meets the program's efficiency requirements at the specified test loads, helping you compare energy waste and operating costs.
With support for the ATX 3.0 standard, the Toughpower GF3 is an excellent choice for anyone looking to upgrade to newer graphics cards, ensuring compatibility with the latest hardware releases.
The fully modular cabling on the Toughpower GF3 allows for easy customization and cable management, optimizing airflow and minimizing clutter in my build.
The ultra-quiet design of the Toughpower GF3 makes it an excellent choice for anyone looking for a power supply that won't add excess noise to their system, even under heavy workloads.
10-year warranty.
This series of power supplies comes in power outputs including 750, 850, 1000, 1200, 1350 and 1650 watts. Choose the wattage option that meets or exceeds the recommendation for your configuration above.
Recommended 850 Watt PSU
Choose this model for a configuration whose recommended wattage above is 850 W or less.
MSI MPG A850G Gaming PSU
MSI MPG A850G Gaming PSU Power (Watts): 850 Efficiency: GOLD 80 PLUS Warranty: 10-year The MSI MPG A850G Gaming Power Supply on Amazon
is our recommended 850 watt PSU.The GOLD 80 PLUS efficiency rating of the MSI MPG A850G PSU was impressive, as it ensures high efficiency, reduces energy consumption, and helps lower energy costs.
The fully modular cabling of the MSI MPG A850G PSU makes customization easy, allowing for better airflow and a cleaner build by minimizing cable clutter.
The near-silent operation of the MSI MPG A850G PSU during low usage was a standout feature, delivering a quiet and distraction-free experience with our PC build.
It also comes with a 10-year warranty, offering us peace of mind and reassuring durability.