what is memory timing?

i am puting together my own computer and i be curious what the timing for memory does (eg 4-4-5-7), how do i change it, and do i obligation to change it?

what is memory timing?

when buying RAM most relations who really want the best will pay attention to the RAM's CAS latency, and here is explanation from it from AMD:



CAS Latency

Certainly, one of the most vital timings is the CAS Latency, which is also the one most people become conscious. Since data is habitually accessed sequentially (same row), the CPU stipulation only select the subsequent column in the row to find the next piece of facts. In other words, CAS Latency is the delay between the CAS signal and the availability of valid notes on the data pins (DQ). The latency between column access (CAS) then plays an noteworthy role in the ceremony of the memory. The lower the latency, the better the performance. However, the memory modules must be capable of support low-latency settings.