What provides voltages of 3.3V, 5V, and 12V to the motherboard?

The correct answer highlights the role of the ATX12V P1 Connector, which is indeed a primary connection point that provides essential voltages to the motherboard. The ATX12V P1 Connector supplies multiple voltages, including 3.3V, 5V, and 12V, which are crucial for different components on the motherboard to function properly. This versatility is vital because different parts of the system, such as the CPU, RAM, and graphics cards, require varying voltage levels to operate efficiently.

In the context of this question, the Power Supply Unit (PSU) is responsible for converting AC power from the wall outlet into the various DC voltages required by the computer, but it is not the direct supplier for the motherboard's voltages. The Power Supply Unit delivers power through connectors, including the ATX12V P1 Connector which physically carries the necessary voltage to the motherboard.

While the term "Motherboard Connector" may somewhat imply a connection carrying power, it is too vague and does not specifically identify the ATX12V P1 Connector, which designates a particular standard and its corresponding pin layout and voltages.

The CPU Power Connector, while essential for supplying additional power specifically to the CPU, does not cover