Low-profile registered ECC DDR333 or unregistered ECC DDR333?

Discussion in 'Asus' started by D. Jones, Apr 2, 2004.

  1. D. Jones

    D. Jones Guest

    Is there a way to tell if my memory is registered, other than just by looking at the DIMM? I purchased what are supposed to be two matched 512mb DDR333 Registered ECC modules (the memory ICs on the PCBs are Samsung brand), but they're the same height as a regular unregistered module. Does unregistered DDR333 ECC memory exist?
     
    D. Jones, Apr 2, 2004
    #1
    1. Advertisements

  2. D. Jones

    Paul Guest

    As far as I know, you'll find

    unbuffered with no ECC (say, for example, 16 chips on a 512MB DIMM)
    unbuffered with ECC (say, for example, 18 chips on a 512MB DIMM)

    For those two, sometimes the same DIMM PCB is used, and the difference
    is whether they fill all the locations on the DIMM with chips or not.

    For registered memory, I would expect to see it with ECC. There would
    be a similar number of chips, plus the addition of some different
    dimensioned chips to do the "registering" and one chip that is a
    phase locked loop (to buffer up copies of the clock signal, for
    distribution on the DIMM).

    Here is a registered DIMM with ECC which is 1.2" high,
    has 18 memory chips, 2 buffer chips, and 1 PLL chip. I
    guess this is possible if "skinny" memory chips are used:
    http://www.valueram.com/datasheets/KVR266X72RC25_512D.pdf

    Here is a registered DIMM with ECC which is 1.7" high,
    has 18 memory chips, 2 buffer chips, and 1 PLL chip. The
    memory chips are probably as wide as the ones in the
    next two examples - an older design:
    http://www.valueram.com/datasheets/KVR266X72RC25_1024.pdf

    This is unbuffered with ECC - 18 memory chips:
    http://www.valueram.com/datasheets/KVR266X72C25_512.pdf

    This is unbuffered with no ECC - 16 memory chips:
    http://www.valueram.com/datasheets/KVR266X64C25_512.pdf

    HTH,
    Paul
     
    Paul, Apr 2, 2004
    #2
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.