Originally Posted by vibraslap
FWIW, the actual chips in these DIMM's are rated at 2133 by the actual manufacturer(Samsung), and then they are binned by G-skill and sold at whatever speed they could get reliably stable.
But, in the end, the performance index (MHz / CL) is pretty similar across all the high-end kits, right? Nobody's selling 3600MHz @ CL13, I mean, haha. Or, are you saying, DRAM binned at a higher frequency will be able to run lower & tighter than a chip binned at the lower frequency? OK, wait, that makes sense.
All the sticks are sold at 1.35V; they reach their binned frequencies at that voltage. So, a chip that can do 3733 @ 1.35V is obviously better binned than a chip that can 3200 @ 1.35V, even if we ignore the timings.
Regarding CR1/2 (1T/2T), I found this article
(but it's on DDR3 on AMD IMC
): apparently, CL & CR & tRFC & tREF have the largest impacts, about 1% each.