asrock pro 3 motherboard vs power supply issue

Hello,

i recently acquired an asrock pro 3 for a project budget build for a friend and have a query...

Basically, the atx 12v interface for the board has 8 pin holes, however my power supply has a 6+4, so

if i only connect the 6 to the 8 holes will it work?
if i connect 8 and have two pins overhanging will that work?
do i need to buy and adapter for 6 to 8 or 10 to 8?

thanks