It's the CPU, not the motherboard, that determines if your system supports 64 bit.
That said, any CPU made in the last few years is 64 bit capable.
Not exactly true. There are plenty of older MOBO's with a 32-bit Chipset that had a 64-bit CPU's and the 'problem' aka limit was the Chipet.
Current MOBO's & Chipsets are 64-bit clean. OP has no worries