Press Windows + R
Type msinfo32 and press Enter
Look for BaseBoard Manufacturer, BaseBoard Product, and BaseBoard Version
Open Command Prompt
Type wmic baseboard get product,Manufacturer,version,serialnumber and press Enter
Check the motherboard label inside the PC case
Use CPU-Z and open the Mainboard tab
Use Speccy and view the Motherboard section
Check the motherboard box or purchase receipt
Check the BIOS/UEFI screen during startup