A toolkit for providing detailed system information and diagnosing various PC components. There are 13 benchmarks, 34 modules with detailed information, support for a huge number of different devices and much more.
3DMark Basic Edition is a free version of one of the most famous benchmarks, offering the user a number of 3D graphics and CPU stress tests, with which you can evaluate the performance and stability of a computer
Sysinternals Suite - a large set of useful tools for diagnosing and troubleshooting various kinds of system problems from Mark Russinovich, a well-known technical specialist, co-founder of Winternals Software, and now an employee of the company
OCCT (OverClock Checking Tool) is very appreciated among the so-called oveclockers a tool to test the underlying computer components that have been "overclocked" to achieve the highest possible performance. It also provides detailed information, including about your processor.