Rivatuner has been updated towards version 2.23 This release has a number of updates and fixes. But please do check out the changelist.

RivaTuner is a complete powerful tweaking environment, providing you everything you may need to tune NVIDIA GPU based display adapters. The widest driver-level Direct3D / OpenGL and system tuning options, flexible profiling system allowing to make custom settings on per-application basis, both driver-level and low-level hardware access modes, unique diagnostic and real-time hardware monitoring features and exclusive power user oriented tools like built-in registry editor and patch script engine.

For novice users, we have a guide to help you through Rivatuner and setup fan speeds and overclocks on your graphics card. This guide will hopefully help you understand how to use the features that Rivatuner provides.