Background: I'm a 3D artist (as a hobby) and have recently started using Ubuntu 12.04 LTS as a dual-boot with Windows 7. It's running on my a fairly new 64-bit Toshiba laptop with an nVidia GeForce GT 540M GPU (graphics card). It also, however has Intel Integrated Graphics (which I suspect Ubuntu's been using). So, when I render my 3D scenes to images on Windows, I am able to choose between using my CPU or my nVidia GPU (faster). From the 3D application, I can set the GPU to use either CUDA or OpenCL. In Ubuntu, there's no GPU option. After doing (too much?) research on the issues with Linux and the nVidia Optimus technology, I am slightly more enlightened, but a lot more confused. I don't care one bit about the Optimus technology, as battery life is not by any means an issue for me. Here's my question: What can I do to be able to use CUDA-utilizing programs (such as Blender) on my nVidia GPU in Ubuntu? Will I need nVidia drivers? (I have heard they don't play nicely with Optimus setups on Linux.) Is there at least a way to use OpenCL on my GPU in Ubuntu?