How many pins did the first p1 power connector to the motherboard have that was used with the original atx?

The first P1 power connector to the motherboard have that was used with the original ATX contained a 20-pin P1 connector.

The 20-pin ATX style connector or the Molex 39-29-9202 is the industry standard ATX power-supply–to–motherboard main connector. It is utilized in the SFX form factor or any other ATX-based variations and was first used in the ATX form factor power supply.

The ATX standard recommends the colors for the wires that are listed in Table 3.3, however, they could vary from manufacturer to manufacturer since they are not required for compliance to the specification. The pins are arranged looking at the back of the connector (from the wire and not terminal side) as shown in the table since it shows that its orientation if the connector plugged in was back-probed.

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im sorry i dont know