The supplemental PCIe power feature complements the ATX 3.1 power standard ... beyond the system's typical 12V power supplied by the 24-pin connector. While the 24-pin connector handles PCIe ...
The ATX power connector with the mainboard was increased from 20 to 24 pins to allow for more 12 V capacity to be added. Along with the Pentium 4’s appetite for power came the new 4-pin ...
It’s all wrapped up in a neat slant-sided 3D-printed case that fits onto the ATX power supply itself. The result is a neat and tidy power supply built out of readily-available components.
That combines with the existing 168 W of board power delivered by the 12V rail in the main 24-pin ATX power connector to provide a grand total of 420 W. Note, that's 420 W just for the PCIe slots ...