Read the whole thing, problem here is you haven't offered any exact description of your ram. The specific model is neccessary, cpu-z can be used to read the data from the spd area of the chip. This will provide the standard settings which are jedec values at 1066, then there will be enhanced modes listed of the equivilent in xtended language used by intel.
I looked around and saw 2 sets very quickly, one runs at 1.65v with cas of 9, the other set uses 1.65v with a cas of 7. This is at the highest rating of the chip, when running at 1333.
You need to provide model number of your chip.
There is also some confusion in reading your material which suggests your using 2 sets of ram and each is different.