Pentium works on Windows and Intel Pentium class and AMD
CPUs to determine the CPUID information such as the vendor,
brand/model, step, model, instruction set family, cpu serial
number, and the RDTSC Time stamp register for high
resolution timing measured in CPU cycles since the last
boot. It is designed to be incorporated in your own Java
progams.

You can also use it as a standalone utility with:

java.exe -jar pentium.jar

The nativepentium.dll must be on the path, e.g. in the
current directory. In JDK 1.5, the DLL can be in the jar so
long as it has no package path.