KNOWLEDGE BASE

Tips, tricks, and trends about PCs, hardware, and gaming. From professionals, for you.

Gaming PC buying guide: The right power supply

published 02.05.2024 | updated 10.03.2025 | Categories: Gaming, Hardware, Guides | Advertisement


Most people focus on the obvious contenders, e.g. graphics card and processor, when putting together their gaming PC. But the power supply unit («PSU for short») is actually the beating heart of every PC. And there are so many to choose from. So which PSU is the right fit for your gaming PC? The answer comes down to several factors. Our guide is here to tell you what you need to look out for when deciding and which power supplies we recommend.

Why does the power supply matter for gaming PCs?

One thing’s clear: nothing works on a PC without a power supply! However, a high-quality power supply does more than provide stable power. The wrong PSU can compromise performance and even lead to hardware damage. So choosing the right one is crucial for ensuring your gaming PC's durability, performance, and efficiency.

A number of factors play a role when it comes to choosing a power supply. To keep it straightforward and make your decision easier, we're going to focus on the three most important ones:

  1. Power (watts)
  2. Energy efficiency
  3. Connectivity

How many watts does my gaming PC need?

Many gamers and PC manufacturers go for the («more is better») approach and opt for power supply units with excessively high wattages. As well as being unnecessarily expensive, this can also have a negative impact on efficiency (→ more on efficiency). The power you need from a PSU depends on the components of your specific PC.

The PSU for an entry-level gaming PC should deliver at least 500 watts, for high-performance high-end PCs at least 700 watts. General rule: add together the wattage of your main components (CPU, graphics card, etc.) and factor in an extra 20-30% buffer for future upgrades and peak loads.

Tip: If you don't want to do the maths yourself, the Seasonic watt calculator is here to help. It gives you specific recommendations for suitable power supplies based on your components.

What happens if a power supply isn't powerful enough?

The most obvious sign that your power supply isn't delivering enough watts: your PC just shuts down and restarts. This happens when power spikes occur, for example when the graphics card is suddenly under load from games or other demanding applications. Regular crashes aren't good for the hardware and data can be lost. That's why a power supply with sufficient power is important for your gaming PC.

How does energy efficiency apply to power supplies?

Power supplies are categorised according to their energy efficiency, with 80 PLUS being the most commonly used certification system. 80 PLUS means that at least 80 % of the electricity that the PSU draws from the socket reaches the components. The higher the rating, the more efficient the power supply unit is. This lowers energy costs, reduces waste heat and noise, and extends service life.

Remember: Higher efficiency = more (%) power is utilized = less power is lost in waste heat.

20% UTILIZATION

50% UTILIZATION

100% UTILIZATION

80+ BRONZE

82%

85%

82%

80+ SILVER

85%

88%

85%

80+ GOLD

87%

90%

87%

80+ PLATINUM

90%

92%

89%

80+ TITANIUM

92%

94%

90%

Tip: A utilization between 20% and 80% is ideal for optimal efficiency. The power supply unit should therefore have neither too much nor too little power (watts).

We recommend the following for gaming PCs, depending on your focus:

  • Best price/performance ratio: 80+ GOLD
  • Low heat and noise generation: 80+ PLATINUM

What connectors does a gaming power supply need?

You don't need to worry about connectors for a «standard gaming PC». Current high-quality PSUs have all the connectors necessary for the most important components:

  • 24 pin ATX connector for the motherboard
  • PCIe (8 pin / 6+2 pin) for the CPU and GPU
  • SATA for SSDs and HDDs

Important: Most gaming PCs now use M.2 SSDs, which don't need an extra power cable. If you use several SATA SSDs or hard drives, make sure there are enough SATA connectors.

Modular v non-modular power supplies

Modular power supplies give you the option of just connecting the cables you need. This results in a cleaner look and better air circulation. Non-modular power supplies have all cables permanently fixed in place, which makes them cheaper but also means things can get untidy. Ultimately, the choice comes down to budget and taste. We recommend fully modular power supplies for maximum flexibility and future upgrades.

What is ATX 3.0 / ATX 3.1 and which gaming PCs need it?

ATX 3.0 is the latest standard for power supply units and is particularly relevant for high-end components with high power consumption, such as NVIDIA RTX 40 GPUs. The new 12VHPWR power connectors are more compact than the previous 8 pin PCIe connectors and can also deliver more power. Plus, ATX 3.0 power supplies can absorb significant power spikes, preventing the PC from shutting down during intensive gaming  (→ more on problems related to weak power supplies).

If you're planning on using a top-of-the-range graphics card or want to make substantial upgrades to your PC in future, an ATX 3.0 power supply is a smart investment.

The best power supplies for gaming PCs: Seasonic

So, which PSU is the right fit for your gaming PC? Drawing on the experience of thousands of Joule Performance-built gaming PCs, one brand stands out in particular: Seasonic. Specialist PSU manufacturer Seasonic has stood for quality and innovation in the power supply market for over 40 years. 

Seasonic power supplies cover all key aspects:

  • Variable performance: Seasonic offers a wide range of PSUs with different power ratings, from 500 watts to well over 1000 watts; from entry-level models to PSUs for demanding high-end gaming PCs and professional workstations.
  • Energy efficiency: With a variety of 80 PLUS Gold, Platinum and even Titanium models available, Seasonic power supplies have an extremely high energy efficiency. This means they produce little waste heat and stay pleasantly quiet, even under load.
  • State-of-the-art connectors: Seasonic leads the way in ATX 3.0 power supplies for the next generation of hardware. All cables, plugs, and connectors are top quality. And most models are fully modular, which makes clean cable management a breeze.
ATX 3.0 ist die neueste Technologie für Gaming PC NetzteileATX 3.0 ist die neueste Technologie für Gaming PC Netzteile
  • Plus reliability! Our service statistics on thousands of built gaming PCs show that Seasonic power supplies have a very low failure rate. And that's true across all product series and price segments. Our extreme gaming PCs with custom water cooling are also exclusively equipped with Seasonic power supplies because of this unbeatable reliability.

Conclusion: Seasonic power supplies combine high performance, efficiency, and state-of-the-art technology. This makes them an excellent choice for any gamer who doesn’t want to compromise on quality and reliability when choosing a power supply for their gaming PC.


Recommendation: Power supplies for NVIDIA GeForce RTX 40 graphics card

NVIDIA GeForce RTX 40 graphics cards offer gamers high performance as well as unique features and technologies. A power supply is essential to get the best out of your RTX 40 gaming pc. Here are some recommendations for RTX 40 gaming PCs with a focus on budget and best performance:

Tip: Our gaming PC configurator will automatically tell you if your chosen power supply isn't suitable, e.g. if it doesn't have enough power.

Which power supply for RTX 4070 / 4070 SUPER?

Seasonic G12 GC-750 W

With 750 watts, the G12 PSU offers enough power for the RTX 4070 / 4070 SUPER, and there's still room for future upgrades too. Especially if budget matters more than looks or modularity, the G12 series is your best choise.

Seasonic Focus GX, ideal für Nvidia RTX 4070 GrafikkartenSeasonic Focus GX, ideal für Nvidia RTX 4070 Grafikkarten

Which power supply for RTX 4080 / 4080 SUPER?

Seasonic FOCUS GX-850 W

Seasonic VERTEX GX-850 W ATX 3.0

Both power supplies offer 850 watts, 80+ GOLD efficiency, and other high-performance quality for the RTX 4080 and RTX 4080 SUPER. The VERTEX GX featuring the new ATX 3.0 standard is a great alternative if you want to push your RTX 4080 to its limits.

Seasonic Vertex GX, ideal für Nvidia RTX 4080 GrafikkartenSeasonic Vertex GX, ideal für Nvidia RTX 4080 Grafikkarten

Which power supply for RTX 4090?

Seasonic VERTEX PX-1000 W

NVIDIA recommends at least 850 watts. For an RTX 4090 plus high-end CPU, you should choose 1000 watts. ATX 3.0 isn't a must have, but if you want to maximise performance, go for this future-proof version. The Platinum efficiency also reduces heat and noise in high-end PCs.

Seasonic Prime PX, ideal für Nvidia RTX 4090 GrafikkartenSeasonic Prime PX, ideal für Nvidia RTX 4090 Grafikkarten

Recommendation: Power supplies for NVIDIA GeForce RTX 50 graphics card

The latest NVIDIA RTX 50 series sets new standards in gaming performance and efficiency. With higher power demands and innovative technologies, choosing the right power supply is crucial to ensure stability and maximum performance for your gaming PC. Here are some recommended power supplies tailored to different RTX 50 series graphics cards.

Tip: Our gaming PC configurator will automatically tell you if your chosen power supply isn't suitable, e.g. if it doesn't have enough power.

Which power supply for RTX 5070 / 5070 Ti?

Seasonic CORE GX-650 / 750 W

A gaming PC with RTX 5070 / 5070 Ti GPU requires at least 650 / 750 watts. The CORE GX provides this power, is 80 PLUS Gold certified, and offers a cost-effective solution. Seasonic’s CORE series delivers solid performance at an affordable price.

Seasonic Focus GX, ideal für Nvidia RTX 4070 GrafikkartenSeasonic Focus GX, ideal für Nvidia RTX 4070 Grafikkarten

Which power supply for RTX 5080?

Seasonic FOCUS GX-850 W ATX 3.1

The RTX 5080 has a TDP of 360 watts. The FOCUS GX-850 ATX 3 with 850 watts and ATX 3.1 support offers sufficient power and comes with an 80 PLUS Gold certification. The FOCUS series is praised for its excellent price-performance ratio and compact design.

Seasonic Vertex GX, ideal für Nvidia RTX 4080 GrafikkartenSeasonic Vertex GX, ideal für Nvidia RTX 4080 Grafikkarten

Which power supply for RTX 5090?

Seasonic VERTEX PX-1000 W

The RTX 5090 is a beast and needs to be fed accordingly! The VERTEX PX-1000 provides 1000 watts and features a 80 PLUS Platinum certification for maximum efficiency. Seasonic's VERTEX series is known for its premium quality and reliability for powerful high end systems.

Seasonic Prime PX, ideal für Nvidia RTX 4090 GrafikkartenSeasonic Prime PX, ideal für Nvidia RTX 4090 Grafikkarten

Our trust promise:

Sponsored – yes. Bought – no! At Joule Performance, we know how important trust is when choosing components for your gaming PC. That's why, when it comes to our guides, we only choose sponsors whose products we fully support – based on many years of experience, rigorous testing, and the feedback from thousands of customers. Our aim is to provide you with valuable insights and helpful recommendations for your best ever gaming experience!


Matching products: