Dmidecode reports information about your system's hardware as described in your system BIOS according to the SMBIOS/DMI standard. This information typically includes system manufacturer, model name, serial number, BIOS version, asset tag as well as a lot of other details of varying level of interest and reliability depending on the manufacturer. This will often include usage status for the CPU sockets, expansion slots (e.g. AGP, PCI, ISA) and memory module slots, and the list of I/O ports (e.g. serial, parallel, USB).
Sample output from dmidecode can be found here.
In a perfect world, all manufacturers would write accurate and complete DMI table entries in the BIOS. Then people could do useful things like inventory all the PCs in the enterprise down to a tag number in the blink of an eye. Alas, the amount and accuracy of information provided varies from manufacturer to manufacturer, and from model to model. The dmidecode project provides the means to learn exactly what claims your BIOS is making about your hardware. Strange as it might seem, it's useful information, even when it's not 100% reliable.
Three additional tools come with dmidecode:
- biosdecode prints all BIOS related information it can find.
- ownership retrieves the "ownership tag" that can be set on Compaq computers.
- vpddecode prints the "vital product data" information that can be found in almost all IBM computers.