Contradictory RAM clock speeds

Contradictory RAM clock speeds

I have a Asus U32U Rx012D. Here is the relevant specification :
Memory : DDR3 1333/1066 MHz SDRAM, 2 x SO-DIMM socket for expansion up to 8 GB SDRAM *1
My processor is an E450 which means DDR3 1333 and 1066 support is present. The RAM chip in the laptop is the manufacturer installed chip.
However, when checking the RAM speeds, the speed that I am seeing is 667MHz.
asheesh@ashrj-U32U:~$ sudo lshw -C memory
  *-memory
       description: System Memory
       physical id: 26
       slot: System board or motherboard
       size: 2GiB
       capacity: 2GiB
     *-bank:0
          description: DIMM DDR3 Synchronous 667 MHz (1.5 ns)
          product: HMT325S6CFR8C-H9
          vendor: Hynix Semiconduc
          physical id: 0
          serial: 32C0EB88
          slot: A1_DIMM0
          size: 2GiB
          width: 64 bits
          clock: 667MHz (1.5ns)
     *-bank:1
          description: DIMM Synchronous [empty]
          product: Array1_PartNumber1
          vendor: A1_Manufacturer1
          physical id: 1
          serial: A1_SerNum1
          slot: A1_DIMM1
Even the motherboard A50M doesnt support clock speeds below 800MHz.
Why this discrepancy in clock speeds?