2 x DDR3 DIMM sockets supporting up to 64 GB of system memory
* The maximum 64 GB of system memory can be supported using 16 GB (or above) memory modules. GIGABYTE will update the memory support list on the official website when the memory modules are available on the market.
* Due to a Windows 32-bit operating system limitation, when more than 4 GB of physical memory is installed, the actual memory size displayed will be less than the size of the physical memory installed.
Dual channel memory architecture
Support for DDR3 2400(OC)/2133/1866/1600/1333 MHz memory modules
Support for AMD Memory Profile (AMP)/ Extreme Memory Profile (XMP) memory modules

https://www.gigabyte.com/Motherboard/GA-F2A68HM-S1-rev-10#sp