What is the different between 2 x 8pin and 3 x 8pin for 12VHPWR?
Both 2 x 8pin and 3 x 8pin can deliver full 600w. This is assuming that your PSU wattage is adequate according to your PSU manufacturer guidelines.
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. (RTX 4090 is a 450w card)
But 3 x 8pin will give you an extra redundancy for the power being supplied to the GPU and making use of 3 x 12V rails assuming you are using a multi-rail PSU.
So, in general we would recommend using 3 x 8pin for 12VHPWR.
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. (RTX 4090 is a 450w card)
But 3 x 8pin will give you an extra redundancy for the power being supplied to the GPU and making use of 3 x 12V rails assuming you are using a multi-rail PSU.
So, in general we would recommend using 3 x 8pin for 12VHPWR.
Updated on: 26/10/2022
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