Letter after PC speed

ClassicD

Honorable
Nov 20, 2013
43
0
10,540
Hi,

I had a nightmare trying to update the RAM on a HP SFF PC.
The RAM installed was PC3-10600 - when i tried to update the same speed it would not take.
Looking closer it was 10600U, My thought this means Unbuffered?? I was using memory that didn't have the 'U'. I thought Memory without a letter would be standard, Non-ECC, unbuffered?


My question is what does the letter means after the PC speed, I have seen the letters E,R,U,S

My assumption is ECC,Registered,Unbuffered, s=???


Thanks
 
I have an SO-DIMM with the letter 'S'

Also i have multiple 240 pin Sticks with 'R' and 'E' and 'U'

What do these letters mean, do they have any significance as they were all from non-server computers.