CPU Free BenchMark (CPUMark) Download
CPU Free BenchMark includes testing registries, FPU & ALU. There are 3 major tests (registry, floating-point operations & integer operations). Each test is built based on some equations & operations depending on the test.
Every major test contains 3 identical tests. For every identical test the seconds & milliseconds are calculated. At the end of a major test, an arithmetic average is made from the seconds & milliseconds times saved from those 3 tests. So if you get a wrong time at a "mini"-test the other 2 can make the error be ignored.