Geekbench is an essential cross-platform benchmark for Windows, Linux, and Android that you can use for measuring the performance of your PC's processor and RAM.
You can access multi-threaded benchmarks that can run in single-threaded and multi-threaded modes, letting you see the performance increase multiple cores (or multiple processors) bring to your system. It is available in 32-bit and 64-bit versions, so you can run both versions on a 64-bit operating system and see the overall increase 64-bit applications bring to your system.
Geekbench features some benchmarks that utilize SIMD instructions (Altivec and SSE), allowing you to see performance increases SIMD-aware applications bring to your system. It can also be used in both Universal and Rosetta versions (Mac OS X). Run the Rosetta version on your Intel-based Mac to see how quickly it runs PowerPC applications or to find out the performance advantages Universal apps bring.
Want to see how your rig measures up against other users? You can use the Geekbench Result Browser to compare your scores with other Geekbench users.