You will need to have the 2x4 power connector, else you will have power issues if you use the 1x4 connector.
Also, system may power up fine if you are using an adapter, but you will have some powers issues at later stages.
It's better to is the recommended 2x4 power connector.
Please also refer to the motherboard manual for minimum power considerations for this board. Minimum power requirement is 460W.
Hope this will be helpful to you.