The accepted answer of the thread How do I check system specifications? is about System Monitor → System in 11.04. However, there is no tab System anymore in the application System Monitor of Ubuntu 15.10. I still want to do the checking by default tools, not by external installations.
How can you check system specifications in Ubuntu 15.10?
You can find some info under System Settings → Details → Overview. It gives you some details about your RAM, Processor, OS Type and hardrive.
If you want something more complete you can install HardInfo via terminal:
sudo apt-get install hardinfo
It gives you a very complete description about your system.
Have a nice day!
