PC hardware forum: Power Supply Disaster (Help needed immediately)

The additional power connector is for the P4 CPU - supplies power directly to the processor. Without it, the P4 processor will not run. PS's for P4 motherboards require a special cable called the ATX12V,
a 2x2 array that connects directly to the voltage regulator module VRM) on the motherboard.

Technically speaking:
System design based on Pentium 4 processors will require a new power supply. A new superset of the original ATX power supply is now defined and called, ''ATX12V.''

The new +12V power connector enables the delivery of more +12 VDC current to the motherboard. The presents of the +12V 4-pin connector indicates that the power supply is an ATX12V. The absence of the +12V 4-pin connector indicates that the power supply is an ATX.

Increased +12VDC output is due primarily to the higher power conversion and transmission efficiencies of +12VDC relative to +5VDC or +3.3VDC. Components on the motherboard having unique voltage requirements are expected to be powered by DC/DC converters of the +12VDC power supply output.

An ATX power supply supports motherboards that rely on DC/DC conversion from +5 VDC and +3.3VDC. However, an ATX12V power supply supports motherboards that rely on DC/DC conversion from +12VDC, +5VDC, or 3.3VDC yielding more application flexibility for future platforms.

ATX12V power supplies should be backward compatibility to existing ATX motherboards. ATX12V power supplies are expected to maintain the +5VDC and +3.3VDC output capability.

IT IS REQUIRED THAT ALL PENTIUM 4 PROCESSOR-BASED PLATFORMS USE POWER SUPPLIES HAVING A +12VDC 4-PIN CONNECTOR FOR INCREASED CURRENT SPECIFICATIONS.

You were lucky when that the old PS did not burn anything attached to the Power Supply. It very well could have destroyed everything connected to it.


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