i7z is a wonderful tool if you are using a Intel Core i3, i5 or i7 CPU. It shows a whole bunch of information about each physical (not hyper-threaded) core of the CPU: its actual frequency, C-state and temperature. The frequency and C-state info is especially useful since these modern Intel CPUs use Speed Step, Turbo Boost and a lot of other technologies to get the maximum performance and minimum power consumption.
$ sudo apt install i7z
$ sudo i7z
Ctrl + C to quit its interface.
Tried with: i7z 0.27.2 and Ubuntu 15.10
There are many GUI tools (like i-Nex) and commandline utilities in Linux to look up system information. To get information about the CPU, I like
lscpu. The reason being that its name is the easiest among all tools to remember. It shows information about the CPU vendor, architecture and cache sizes.
If you find that this tool is not present on your system, just install the
$ sudo apt install util-linux
Tried with: Util-Linux 2.20.1 and Ubuntu 14.04
The easiest way to get information about your CPU is:
$ cat /proc/cpuinfo
This lists out all the details of every CPU core detected by the Linux OS.
To just get the model of your CPU:
$ cat /proc/cpuinfo | grep "model name"
Tried with: Ubuntu 14.04
There are now websites which offer performance comparison between any two CPUs or GPUs. The one I like is CPUBoss for CPU comparison and GPUBoss for GPU comparison. In either site, you can also find out information about an individual CPU or GPU by searching for its name in the top search box. You can also sort all the CPUs or GPUs by their performance or other metrics by using the Sort option at the top.
Sometimes, you might find it useful or educational to know the microarchitecture of a given CPU. That is, given the brand name of a CPU like
i7-2600K, you might want to know the underlying microarchitecture of that CPU.
I found that the easiest way is to search for the CPU name at the Identify page of CPU World. The search returns some basic information about the CPU. But, at the bottom your CPU should be listed in the Related Pages section. Clicking on its name here shows a page with detailed information about your CPU. Here, you can find the microarchitecture, processor core and stepping information for your CPU.