dmidecode

dmidecode is a tool for dumping a computer’s DMI (some say SMBIOS ) table contents in a human-readable format

get memory information

manufacturer, parts, speed, type, voltage etc.

dmidecode -t memory

mainboard slot information (m2 slots)

get everything about available slots on a system, such as pci express slots or m2 slots and their desgination:

dmidecode --type slot
dmidecode --type slot|grep "Designation: M2"