A memory system is provided, which includes a nonvolatile memory module including a plurality of nonvolatile memory devices, and a memory module controller configured to control the nonvolatile memory module. At least two nonvolatile memory devices of the plurality of nonvolatile memory devices are configured to store serial presence detect (SPD) information. The memory module controller is configured to read the SPD information from the nonvolatile memory module and to set a communication mode with the nonvolatile memory module based on the read SPD information.