CPU-X

CPU-X is a Free software that gathers information on CPU, motherboard and more.

CPU-X is a system profiling and monitoring application (similar to CPU-Z for Windows), but CPU-X is a Free and Open Source software designed for GNU/Linux and FreeBSD.

It can be used in graphical mode by using GTK or in text-based mode by using NCurses. A dump mode is present from command line.
CPU-X reports informations about:
Screenshot (light) Screenshot (dark)
You can download lastest CPU-X version here.
Read more about this software on README.
Don't forget to visit wiki page for screenshots and installation instructions!