EPS vs PCIe 8-pin

EPS and PCIe 8-pin are two 8-pin 12 V power connectors that look alike and do not interchange. EPS comes from the EPS12V server power supply specification and names the 2x4 CPU power connector, also called CPU 8-pin. The PCIe 8-pin is the 2x4 auxiliary power connector for add-in cards. Intel's design guide gives the PCIe 2x4 plug unique mechanical keying to block a plug meant for a different connector.

Intel's ATX pinout gives the CPU connector four +12 V pins and four grounds. NVIDIA's table gives the PCIe 8-pin three 12 V pins, two sense pins and grounds. A PCIe 8-pin is rated 150 W, and NVIDIA found it can carry up to 175 W, which needs at least 18 A from the supply. Workstation cards use both types. The RTX A6000 is a 300 W card with a CPU 8-pin (EPS-12V) input, while the RTX A5000 and A5500 are 230 W cards with a PCIe 8-pin.

Match the connector name on the card's spec sheet to the port on the supply. A card listing CPU 8-pin needs an EPS cable. NVIDIA documents an adapter that joins two PCIe 8-pin connectors into one CPU 8-pin, for supplies short on EPS ports.

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Last verified October 30, 2026.