I wouldn't use unbuffered, even though the MPX supposedly allows it. For best stability, you'll want to use Registered/ECC modules. The 760MP absolutely requires it (regardless of the success of some with a stick or two of unbuffered) and, while 760MPX supposedly allows you to use unbuffered ... why take any chances? 😀 It's only a couple bucks more and well worth it, IMHO.