dmidecode is a tool for dumping a computer's DMI (some say SMBIOS) table contents in a human-readable format. This table contains a description of the system's hardware components, as well as other useful pieces of information such as serial numbers and BIOS revision. Thanks to this table, you can retrieve this information without having to probe for the actual hardware
dmidecode --type 1 system information : server model, serial
dmidecode --type 4 CPU
dmidecode --type 17 memory device & slot
Reference : howtoforge.com
