Quote, "In computer technology, CAS (column address strobe) is a signal sent to a dynamic random access memory that tells it that an associated address is a column address. A data bit in DRAM is stored in a cell located by the intersection of a column address and a row address. A RAS (row address strobe) signal is used to validate the row address." "In a computer system, latency is often used to mean any delay or waiting that increases real or perceived beyond the response time desired. Specific contributors to computer latency include mismatches in data speed between the microprocessor and input/output devices and inadequate data buffer."
Tier1 means top quality DRAM chips. If you leave your SDRAM timing setting in the BIOS at default (Auto), then there is no point of buying these. They are designed for tweaking and overclocking. It's like putting a 400 horsepower engine in a car only for grocery shopping. Mushkin's basic value DRAM is good enough for most people.