There are a lot of benchmarks and test-/diagnostic programs on the Ultimate Boot CD.
BruteBenchmark
Breakin is Advanced Clustering's stress-test and hardware diagnostics tool.
OpenBenchmarking.org is an open, collaborative testing platform designed by Phoronix Media and the developers behind the Phoronix Test Suite.
Geekbench
Geekbench Browser
Geekbench v4 results:
Memtest86
Memtest86+ based on Memtest86.
Memtest OS X memtest for Apple computers.
Lightsmark
FurMark OpenGL 2.0 test.