Looking to change GPUs

I currently have a Radeon HD 7970 GPU installed and I am looking at buying a NVIDIA GTX770.

I would like to know if the NVIDIA one is better, in particular to WINE gaming, and Blender rendering I know NVIDIA is better, but would like to know how well the Nvidia cards work on Linux, I have only used AMD cards so far.

Whether Nvidia graphics cards are better in Ubuntu than AMD graphics cards is a matter of opinion, but Nvidia graphics cards are more fully supported in Blender than AMD graphics cards.

Cycles is a new render engine available since Blender 2.61. It is still under development, and intends to become a render engine with a focus on interactivity and ease of use, while still supporting many production features. Nvidia CUDA is supported for GPU rendering with Nvidia graphics cards starting from GTX 4xx. Cycles requires recent Nvidia drivers and NVIDIA CUDA toolkit to be installed.

In Ubuntu 14.04 there is a new CUDA package that is not available in Ubuntu 13.10 called libcudart5.5. libcudart5.5 is the NVIDIA CUDA runtime library. libcudart5.5 requires the nvidia-331 or more recent graphics driver.

^{CUDA enabled in Blender in Ubuntu 14.04}