Question 1

What size power supply does the RTX 4090 need?

Accepted Answer

A 750W PSU is recommended for a typical build using the RTX 4090 (which draws about 450W), leaving ~30% headroom for the CPU and other components.

Question 2

Is a smaller PSU enough for the RTX 4090?

Accepted Answer

It can boot on less, but PSUs run most efficiently and reliably below ~80% load, so we recommend 750W rather than the bare minimum.

What PSU does the RTX 4090 need?

Power requirement