There was an interesting question on Gamedev.net today asking about whether there is an API in C# for querying information about the GPUs installed. Apparently, GPU-Z uses the CUDA API to get information about an NVIDIA GPU, and GPUPerfAPI for the AMD GPU. However, a good alternative to those APIs is OpenCL, a platform independent framework to gather information about the computing devices in a PC. For C#, OpenCL.NET works quite well.
The following program queries and outputs the device information from OpenCL. It comes in handy when you need to know some basic properties of the computer you are using when you don’t want to use GPU-Z or CPU-Z.