I'm a bit confused...
I have just bought two additional RAM modules for my desktop computer so now all of the four available slots are occupied. Each module is 2GB.
Before buying I checked my old RAM. According to Speccy they are both DDR2 PC2-8900. Then Speccy lists some JEDEC info:
#3: 555,6 MHz, CL6
#2: 400 MHz, CL5
#1: 333,3 MHz, CL4
Alright, so I thought that if I bought some 800 MHz CL5 mermory, everything would be great. The JEDEC info for the new RAM modules is as follows:
#3: 400 MHz, CL5
#2: 266,7 MHz, CL4
#2: 200 MHz, CL3
So, now the two new modules are running at 400 MHz, CL5 - I understand that with DDR2 RAM the effective frequency is the double so I guess that is OK.
The old modules are running at 555,6 MHz, CL6. That would be 1111,2 MHz when doubled.
I do not get it; why do the old modules not run at 400MHz, CL5? Would that not result in better performance?
You are probably looking at the specs on the RAM in whatever program you are getting the info ! -- a system will not run different modules at different speeds at the same time (all 4 modules are run at the same settings and timings - which is why you need to make sure they can run together - there is no way to have a MOBO run 2 slots at 1 speed and the other 2 at another speed just doesn't work that way !)