What's your mobo and CPU? Have you checked in MSCONFIG to see if the system is limiting DRAM - look in MSCONFIG>BOOT>ADVANCED and see if maximum memory is checked and limiting DRAM, also what OS version, some limit DRAM to 8GB max. If neither of the latter we're back to needing the mobo and CPU to check the DRAM set up
I already attempted to change the max boot ram. The box is already unchecked, but I have tried checking it and putting in 16384MB, still no go.
Motherboard: EVGA Z77 FTW
CPU: Intel i5 3570k
OS: Windows 8.1 64Bit