You'll need to go into the BIOS and hunt for the memory section. There should be an option for selecting an XMP profile for your RAM in there (The higher speed setting). It's essentially overclocking made easy by a preprogrammed profile.
By default, RAM runs at the highest speed possible by the system in the SPD table. XMP, which is what this memory has, gives the table an extra area for running faster but requires a manual selection.
By default, RAM runs at the highest speed possible by the system in the SPD table. XMP, which is what this memory has, gives the table an extra area for running faster but requires a manual selection.