It is necessary to feed the processor and motherboard. We require a 12 V Processor core voltage connector (2x4 pin) and Main power connector (2x12). If you use a power connector for the processor with fewer pins, the system will not work and it could damage the CPU.
On typical power supplies, the two 4-pin connectors are on a single cable and these two connectors together (with retention tabs side-by-side) will plug into the board's 8-pin connector. If they do not, then there is a compatibility issue. If this is an older power supply that only has a 4-pin ATX12V connector, you will need a 4-pin to 8-pin converter cable. These used to be shipped with Intel boards; check your box to see if one is there...