If you just got your hands on the flagship RTX 4090, then you are likely looking for the best PSU to get the most out of it and keep it purring for years to come. This card needs a little more power than its predecessor, with Nvidia recommending at least 850W.
850W may be more than enough for the Founders Edition, however, it is advisable to give yourself a bit of headroom and longevity. If you’re planning on upgrading your gear in the future, or are shopping for the more powerful of the 4090 SKUs, then you should aim for 1000W or more if you can afford it.
Some of these PSUs have rather fancy features, so we have also included a more affordable PSU solution too.
How much power does the RTX 4090 need?
This is the flagship from Nvidia, it is one powerful piece of kit. Because of that, the 4090 comes with a high TDP and this can mean those that were already pushing their old hardware to the limits may need an upgrade.
Others may be building a PC for the first time, bravo, you’ve gone for the don of GPUs. The RTX 4090 graphics card sits with a 450W TDP, 100 more than its predecessor. This is high and while Nvidia recommends a minimum of 850W PSUs, we think you should aim higher to prolong your investment.
Some power recommendations can change depending on the AIB model your GPU is, so always double-check with the relevant manufacturer’s web page so you never end up disappointed.
Best PSU for the RTX 4090: MSI Ai1300P ATX 3
MSI MEG Ai1300P PCIE 5 & ATX 3.0
- ATX 3 / PCIE 5
- Very efficient
- Gives you a lot of headroom
- Future proof
- Overkill
- Expensive
This 1300W ATX 3 PSU could be considered overkill, it is way more power than is actually required. This PSU is for those that want more of an investment for the future, you never know when an even more powerful GPU is going to come along after all. Aside from that, it is one of the best PSUs on the market for those looking to build the fastest gaming PCs. The advantage of such a quality PSU and high wattage is near silence.
It offers complete support for the latest ATX 3.0 specification, an 80 Plus Platinum rating, 100% Japanese 105°C capacitors, and full modularity.
Best ATX 2 PSU for 4090: ASUS ROG Thor 1000W Platinum II
ASUS ROG Thor 1000W Platinum II
- Quality, reliable, and efficient
- OLED panel
- Winning design
- Expensive
- Will require adapter from your 4090
The ASUS Rog Thor 1000W Power Supply features the OLED Panel and comes with the wattage we recommend. This is definitely for those that want every aspect of their system looking incredible but you will have to pay quite a bit for that luxury.
The 1000W model has an 80 PLUS Platinum rating. It has a built-in 0dB cooling feature with dustproof ipx5 fans with RGB heatsinks for improved cooling. The OLED power display means you can monitor your power usage in real-time.
Best Budget PSU for RTX 4090: Corsair RM1000x
- High quality & reliable
- More affordable
- Will need to use your adapter
If you need a budget-friendly option, we recommend Corsair’s highly-reliable RM1000x model. This is fully modular, gold-rated, and the recommended amount of wattage, perfect.
The unit utilizes 100% Japanese capacitors and you can rest assured of the quality, Corsair makes excellent power supplies. This is another ATX 2 model, so you will need to use the adapter but will also save a lot of money.
12VHPWR RTX 4090 connecter
The RTX 4090 GPU has come with a new power connecter and if you want to power it then you will either need to buy a regular PSU and use your adapter, or you can purchase an ATX 3.0 PSU with the new connectors as part of your cable kit.
Do you need to upgrade your PSU for the 4090?
In conclusion, when it comes to supplying your powerful RTX 4090 GPU, a PSU with at least 1000W is recommended, although you could get by with 850W too. The options above are all of the highest quality and are regularly used in our in-house builds.
It’s important to ensure that the PSU you select is compatible with the rest of your system and can support the power requirements of all of your components.