Quote Originally Posted by rusty View Post
But that would be high VTT volts 1.6v wouldn't it ? Or am I missing something ?
If vdim is 1.65 then vtt can't be 1.6v ?
VDIMM needs to be within 0.5v of CPU VTT. But the ideal difference between the two depends on number of modules installed as well as the memory themselves and at what memory frequency and timings used.

Samsung HCF0 2x1GB liked 0.24-0.31v difference
Samsung HCF0 3x1GB liked 0.31-0.40v difference
6x1GB mixed HCF0 and Micron D9GTR liked 0.35-0.45v difference
3x2GB Corsair Dominator GT Elpida 50nm based likes 0.20-0.28v difference - hence the general trend to need more cpu vtt than samsung hcf0 but handle CAS7 timings higher than others