Have two sticks of Samsung 240 pin Memory PC2-6400U-666-12 E3 and one that says PC2-6400S-666-12 E3 .What deos the U stand for and what does the S stand for behind the 6400 ? both are DDR2 looked at the memory section and see no coding there .
Have both S and U memory but did not know the codes for the letters . Like PC2 DDR2 6400U or PC2 6400S .And found different brands use different codes .Yup both ar 240 Pin . for desk top .S is for Laptop . And what does the CT: number stand for on parts ? or what is the CXT number .normally parts have a Model number serail number and a CT number .