NVIDIA RTX 5090 Can Run on 450W, While RTX 5080 Struggles with Just 300W
Solomon Thompson / 4 days ago

With the new NVIDIA RTX 50 Series on the market, users are testing out various configurations to discover how these models work. Currently, the most powerful models of this new Blackwell-based generation are the NVIDIA RTX 5090 and RTX 5080. While both are high-power models, the RTX 5090 seems to be more flexible when it comes to power supply, as it can run on 450W.
Testing the RTX 5090 with Less Power

ComputerBase tested this by using an adapter with three 8-pin connectors to make the RTX 5090 work, instead of the recommended four connectors, which can provide up to 600W. On the other hand, the RTX 5080 does not have such flexibility, as it cannot start with just two 8-pin connectors offering 300W. The RTX 5090 has a TDP of 575W, but it can be reduced to 450W, though with a performance penalty. Meanwhile, the RTX 5080 has a TDP of 360W, but it will not start with only 300W.
Performance Loss with Lower Power Supply
The RTX 5090 tested models were the ASUS Astral and Zotac Solid. Even though the TDP was reduced to 450W, the performance loss was only 5%. However, this is not the ideal configuration for the RTX 5090, which has been released as the most powerful model designed to offer the best performance. For optimal performance, you should calculate the total wattage needed for your new RTX 50, taking into account other components in your system to ensure it has enough power.