row access strobe (memory) (RAS)

The Row Access Strobe(RAS) or Row Address Strobe (RAS) is known as RAS latency and describes how long it takes to read out a row of a memory cell.

The RAS latency describes the waiting time after which a memory cell can be written to or read from again after an access. This latency is directly related to the read/write amplifiers as well as to the line lengths and the nature of the lines. It is also related to the number of memory cells. The more memory cells are connected, the slower the RAS latency.

The latency is a rating for the readout time and depends on the speed of the motherboard's front side bus( FSB). The same applies to the Columm Access Strobe, the CAS latency.