In general, if you want better performance, lower cas latency is better.
CAS and RAS Latency are two ways of measuring speed
CAS (column access strobe) Latency and RAS (row access strobe) Latency
An ad for memory might sometimes give the CAS Latency value within a series of timing numbers, such as 5-5-5-15. The first value is the CAS latency, which would mean that in this case, this module is CL5. The second value is RAS latency.
CAS Latency rating.
CL: (CAS Latency) or Column Address Strobe Latency is a measurement of delay of the chip's process. So the lower the CL number the lower the latency will be. So your answer is cl5.
CAS Latency
i believe it refers to "cas latency"
CL5
Latency. The main latency figure is CAS Latency, also called CL Latency is the number of clock cycles that a RAM chip has to wait after being read or written, before it is ready to be read or written again. A lower latency means less time the computer has to wait before it can do another memory operation.
For DDR(CAS / DATA RATE) * 2000 = X ns(7/1333MHz) *2000 = 10.5 ns
CL7 and CL9 refer to the CAS latency (Column Address Strobe latency) of RAM modules, with CL7 indicating a latency of 7 clock cycles and CL9 indicating a latency of 9 clock cycles. Lower CAS latency, such as CL7, typically allows for faster data access times compared to higher latencies like CL9, resulting in improved performance in memory-intensive tasks. However, the overall impact on system performance also depends on other factors, such as clock speed and the specific use case. In general, CL7 RAM may be preferred for applications requiring higher responsiveness.