Isn't each 8pin PCIE port can only provide 150w?

In fact, each 8pin PCIE port on a modern PSU can supply over 300W from each port. Thus, 2 x 8pin PCIE ports are more than enough to provide 600W for 12VHPWR.

This is why you see PSU vendors are offering 2 x 8pin to 12VHPWR cables which support 600w.

RTX 4090 is a 450w card. 600w means 133% of 450w.

Updated on: 26/10/2022