What voltage does the power supply provide?

The 65W power supply provides single 12V/5A output. The power lead is equipped with ATX12V 4-pin connector (also known as P4-ATX connector). This is perfect setup for industrial mini-ITX boards but many retail boards are equipped with ATX-20/24 connector and you will need to use a DC/DC convertor (see this question).

The PSU is rated at 65W at normal conditions but it can only deliver 40W at 65C, please keep this in mind when building your product. The PSU is equipped with hickup mode protection, meaning it will turn off its output if power threshold is exceeded and then turn itself back on automatically.