The hardware is installed but the software (drivers) that makes that hardware work is not installed. 1 Go to Device Manager: (Control Panel/System and Maintenance/Hardware). 2. Right click Computer (at the top) and choose “Scan for Hardware changes”. 3. Hit the + by Network Adapters. If there is a yellow exclamation mark besides your network card, then uninstall the driver (right click your card and choose Uninstall), reboot and reinstall. If there is no yellow exclamation mark besides the card, you may still need to uninstall and reinstall. If you no longer have the Network drivers (or Windows cannot automatically find them) download them on a flash drive from another computer and point your Hardware Wizard to this.
You can use software tools to determine your PC hardware; I recommend PC Wizard from CPUID and SiSoft Sandra from SiSoftware. But if you’re not familiar with the installation and a newbie PC user, I strongly recommend that you should ask help from an online pc support.