I know it as a P4 power connector. it works for many CPU's.
No FireWire does not need a separate power supply to operate. FireWire is used to connect peripheral devices to a computer.
systems that have the standard ATX motherboards.
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.
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.
If it as a 20 or 24 pin connector and a 4 pin connector then it is a ATX power supply.
the optical drive will connect to the power supply with a connector called molex connecter it is a 4 prong connector
Power Supply Connector
CPUs get power from two places-- From the motherboard through the tiny pins on the bottom of the CPU (Which in turn gets power from the 20 / 24 pin connector that connects tot he power supply) and from a 4 / 8 (Only on the newest boards) - pin connector that directly feeds the CPU a very steady supply of power. Both come from your actual Power Supply.
24 pin connector is required to supply power to the motherboard.
8-pin power supply connector with 150 watts
8-pin power supply connector, 150watts
The atx 12 connector is one of the motherboard power connectors and used for 12 volt power connect for cpu voltage regulator.