RAM running well below spec speed

Discussion in 'PC Hardware' started by quasarpod, Feb 19, 2016.

  1. quasarpod

    quasarpod MDL Novice

    Jul 29, 2015
    I'm having a lot of trouble trying to get my RAM running at it's rated speed, and I would appreciate any advice from the experts.
    I'm using 2 X 4GB Corsair CMZ8GX3M2A1866C9 which is supposed to run at 1333MHz and maybe even 1866MHz. According to Speccy it's running at 666MHz. The CPU is I7 4770 quad core 3.40GHz.
    Motherboard is ASUS Z87-K. I've played around with the frequency settings in BIOS with no luck, haven't touched the processor settings.
    Any advice is appreciated.
    Thanks, Kris
  2. bpwnes

    bpwnes MDL Member

    Aug 11, 2015
    Your ram is running at 1333 MHz at the moment. Sometimes programs running in the OS don't report memory speeds perfectly. I've seen this in AIDA64, Speccy, and a few others. Basically the memory is clocked at 666 MHz but it is DDR (Double Data Rate: two actions are performed every one clock cycle), so 666 x 2 = 1333.

    You have 1866 MHz memory, which means it is rated to run at speeds of up to 1866, but by default most motherboards will run it at the default DDR3 speed of 1333. 1866 is an overclocked value, so you will need to overclock it to actually make it run at 1866 MHz. Your can easily overclock it with XMP, which your memory has and the Z87-K supports.

    So go into BIOS and look for the XMP drop-down menu and see if it has any profiles ("Profile #1" etc.), and try them out. If all goes well and it goes up to 1866, Speccy should say 933 MHz (which if doubled equals 1866).
  3. QuantumBug

    QuantumBug MDL Developer

    Mar 7, 2012
    #3 QuantumBug, Feb 19, 2016
    Last edited: Feb 20, 2016
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  4. quasarpod

    quasarpod MDL Novice

    Jul 29, 2015
    Thank you very much bpwnes. Have changed to XMP in the BIOS which shows one profile. Speccy now shows 933MHz as you expected.
    Many thanks for your help.
  5. TuuS

    TuuS MDL Novice

    Feb 23, 2016
    bpwnes is correct, it's the DDR ram that creates the illusion that it's running slower.

    On an unrelated matter be careful of privately branded ram and generics, they sometimes have substandard chips that will slow down your system