CPUMon a simple and lightweight tool for the desktop that shows the CPU consumption and RAM used in real time. Of course, this can already be done in the “Performance” tab of the Task Manager, but if you are looking for something more simplified, it is a good option.
One of the most interesting features of CPUMon is that it tries not to bother you. It shows a graph in real time of what happens with your CPU, either by cores or the whole processor in general, shows the percentage of use in a sidebar and all this as a small transparent window that by default is on top of the rest of programs, although you can modify their size and behavior in the options of the tool.
And even though it stays above any window you have open, it will never be a problem. CPUMon is designed so that your clicks work through it, and never interfere with your work. If by chance there is a button under the graphic, click on it and it will work without problem.
The fact that the tool is transparent has its own problems. For example, depending on the colors you have just below, it can disappear almost completely. It is true that this program offers many visual adjustments, but for example in the tests that I have done I have not managed to place a solid background color. And that despite the fact that the options indicate that it can be done.
If at any given moment you need to move the graphic, you can do it from the cross-shaped button that will appear when you pass the mouse over it, so that you can place it where it suits you best.
And if you do not want to have it visible on the screen, then you can switch to Tray Mode . Then CPUMon is shown as an icon in the system tray, it gives you basic basic figures of CPU and RAM consumption in a tooltip and allows you to display the graphic with a keyboard shortcut.
Keep in mind that it does not allow you to take precise actions on certain situations (for example, show an alert if the CPU usage exceeds a certain percentage), but if you want a tool that can show you the behavior of your processor in real time. Simplified form and without additions, this is what you are looking for.
There is a paid version of the application. In fact, the program will notify you of it every time you open it, but you can use it for free indefinitely. And as a final point, it works from Windows 98 onwards.