Molex 4-pin Peripheral Power Connector Pinout

Pinout for the standard 4-Pin Molex peripheral power connector

By
Tim Fisher
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Tim Fisher
Senior Vice President & Group General Manager, Tech & Sustainability
  • Emporia State University

Tim Fisher has more than 30 years' of professional technology experience. He's been writing about tech for more than two decades and serves as the SVP and General Manager of Lifewire.

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Updated on August 22, 2022

The Molex 4-pin power supply connector is one of the standard peripheral power connectors in computers today. The power connector itself is a Molex 8981 connector called the AMP MATE-N-LOK.

This is the standard connector for all PATA based hard drives, many high-end video cards, and some older optical drives and other internal devices.

Below is the pinout for the standard Molex 4-pin peripheral power connector as of Version 2.2 of the ATX Specification (PDF).

4 pin peripheral power connector
Wikimedia Commons

If you're using this pinout table to test power supply voltages, be aware that the voltages must be within ATX specified tolerances.

Molex 4-pin Peripheral Power Connector Pinout (ATX v2.2)

Pinout Table for Molex 4-pin Power Connectors
Pin Name Color Description
1 +12VDC Yellow +12 VDC
2 COM Black Ground
3 COM Black Ground
4 +5VDC Red +5 VDC
1:20

How to Test a Molex 4-Pin Peripheral With a Multimeter

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