P1 connector
P1
p1
A 20 pin connector.
The P1 power connector is the first ATX power supplies and motherboards used a single power connector. It also has 20 pins.
BTX motherboards use a 24-pin power connector.
The most common power supply connectors for motherboards will be either a 20 or 24 pin connector. Older unit used less pins like the ATX but the cure standard is the 20 or 24 pin main connector.
P1
systems that have the standard ATX motherboards.
AUX
Many/most motherboards have a separate power connector for the CPU. Check your motherboard's installation instructions to locate the CPU power connector. Then connect the matching power supply cable to the CPU power connector on the motherboard.
To provide extra power for more powerful motherboards.
They are not but good motherboards have different color connectors also they are preshaped in the certain way. It is done to avoid incorrect connections. Each connector can go only in its place.