I'm currently using an RTX 4090 and I'm thinking about adding an RTX 5090 for 3D rendering. My CPU is a 9800x3d and my motherboard is an ASRock X870 Steel Legend. I want to know what kind of power supply I should get to support both cards. Also, what motherboard requirements should I keep in mind? Are there other things I should watch out for?
1 Answer
For dual GPUs like this, I’d recommend a power supply of at least 1200W, ideally going up to 1300W or more for some headroom. You could technically get by with a slightly lower wattage, like 1400W, but it’s better to be safe. If you're not worried about aesthetics, consider using two separate power supplies to split the load. Also, look for a slim 5090, preferably the Founder's Edition, since it gives better airflow. Just remember, when you combine two GPUs, the VRAM is capped at the lowest card's amount, meaning you'll only have 24GB for rendering, not 32GB from the 5090.
Just curious, what impact does the PCIe4x4 limitation have on the 4090 when it’s mainly used for rendering?