Shelby

Shelby Meyer

Article #0053
Written March 18, 2025
AI Enhanced March 18, 2025
Updated July, 19 2025-
Category [BUYERS GUIDE] [EDUCATION]

Choosing the Right Power Supply


power supply

Choosing the Right Power Supply for Your Custom PC

When building a custom PC, selecting the right power supply (PSU) is crucial. While opinions vary, there are key factors to consider to ensure your build runs smoothly and efficiently.

Wattage – How Much Do You Need?

To determine the right wattage, add up the power consumption of your CPU, GPU, fans, drives, memory, AIO cooler, and RGB lighting. You can research exact numbers or estimate.
Once you have a total, add 50–100% more to allow for future upgrades. For example, if your components require 400W, consider a 600W or even 800W PSU. Choosing a higher wattage helps future-proof your system.

Brand Matters

In my personal opinion, I advise clients to stick with one of the well-known and trusted brands, such as:

✅ BeQuiet!
✅ EVGA (These are getting harder to find)
✅ Corsair
✅ NZXT
✅ SeaSonic

Reliable brands ensure safety, durability, and better performance. Some no-name brands may not pass safety testing - typically China.

Does It Have the Right Connectors

Most ATX power supplies include standard connectors for SATA, NVMe, motherboard, and CPU power. However, pay close attention to GPU connectors:
• Older GPUs use PCIe 8-pin connectors.
• Some of the newer GPUs (NVIDIA 40 & 50 series) may require a 12VHPWR connector.
Double-check compatibility with your graphics card!

Non-Modular vs. Modular Cables

• Non-modular PSUs are cheaper, but you’ll have extra cables to manage. This can be challenging if you have a smaller case. You’ll need to squish all the extra cables inside the case.

• Modular PSUs allow you to connect only the cables you need, making for a cleaner, more organized build. They are more expensive but worth it for cable management.

⚠ Warning: Only use the cables that came with your PSU. Mixing cables from different brands can damage your components.

Understanding 80+ Efficiency Ratings

Power supplies come with 80+ ratings, such as:

🏆 Platinum
🥇 Gold
🥈 Silver
🥉 Bronze

These ratings indicate efficiency but won’t make a huge difference for a single PC in terms of electricity savings. If you run multiple PCs (like in an office), the cumulative effect of using a higher-rated PSU can save on energy costs over time.

What to Avoid

No-name or cheap Chinese brands – They often have poor quality control.
When I first started building computers for clients, I purchased a case of 12 budget, Chinese power supplys. I had 7 out of the 12 fail within a year. I had to replace the bad ones for customers. I learned my lesson the hard way. — stick to a trusted brand.

Summary

By considering each of these factors, you’ll choose a power supply that ensures reliability, efficiency, and longevity for your custom-built PC.