What do memory timings mean like X-X-X-X?

OverVolt

Lifer
Aug 31, 2002
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89
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I know the 1st one is CAS latency- which is how many cycles it takes to access the memory. But what do the other 3 mean? I know lower is better but still i wanna be able to tweak my memory but i dunno which timings to fool with. I have a total of 8 Diff Timings in my BIOS.