The Nvidia RTX 4090 remains one of the best GPUs out there in 2024. Not only is it a solid graphics card, but it's also among the biggest and the most power-hungry cards on the market. It's also one of the first GPUs to use the 12VHPWR 16-pin connector, which is now commonly seen on many other RTX 40-series graphics cards, including the new RTX 4080 Super.

While there are some mixed opinions on the 12VHPRW connector, there is no denying that it makes it convenient to power the GPU via a single cable, despite its high power requirements. It is, however, worth noting that not all power supply units have the new 12VHPRW power connector, and it's only limited to the new ATX 3.0 PSUs. But the good news is you don't necessarily need a new power supply for the Nvidia RTX 4090 or even other new RTX 40-series GPUs.

Nvidia RTX 4090 power supply requirements

Rated at 450W, with a minimum PSU requirement of 850W

The Nvidia RTX 4090 Founders Edition from Nvidia is rated at 450W, and the company recommends a minimum of an 850W power supply on your PC with the RTX 4090. However, since you're likely pairing it with some other high-end hardware, realistically, you're going to be looking at 1000W+ to give yourself some headroom.

You don't necessarily have to buy one of the new ATX 3.0 compatible PSUs, as the RTX 4090 comes with an adapter, allowing you to run as many as four PCIe 8-pin (6+2) power cables between your RTX 4090 and basically every power supply out there right now. It's messy, but it works very well and keeps you from spending money on a PSU just to have the new connector.

You don't have to, but you might want to consider it

To make a long story short, you don't necessarily have to buy a new power supply unit for the RTX 4090 just for the new 12VHPWR connector. You can use your existing PSU with an adapter that's bundled with the RTX 4090 as long as it can deliver enough power for the GPU and the rest of the components that are installed on your PC. But if you plan to upgrade your PSU to meet the minimum power requirements, then you might as well consider buying one of the new ATX 3.0 power supplies. The be quiet! Pure Power 12 M PSU that we recently reviewed is one of the best options out there right now, and you can get this with up to 1200W output as well.

It's also worth noting that there is some controversy over the 12VHPWR connector, specifically the adapters being shipped by Nvidia. There are multiple reports of them melting, with bending and poor-quality connections among the issues causing it. Dedicated cables appear to be less susceptible, making it potentially even more valuable to grab an ATX 3.0 PSU if you can.