By the time DDR SODIMMS arrived, some buyers recognized that notebooks could also be high-performance PCs. One ingredient of high performance is optimized memory. There are a number of memory timings that convey the time delays involved in various functions within the module. First and most important among this is CAS latency (CL). This image shows the CL2.5 timing on a Samsung DDR-266 SODIMM. In general, lower timings yield faster performance.