Phoronix takes a look at the performance of the Nouveau GeForce 400/500 Fermi drivers on Linux Kernel 3.1

Besides boosting the Intel Sandy Bridge performance, the Linux 3.1 kernel is also great for open-source graphics in that it has improved support for NVIDIA GeForce 400/500 "Fermi" graphics cards via the reverse-engineered Nouveau driver. The Linux kernel has already supported kernel mode-setting for these GPUs and then more recently there was 2D/X-Video acceleration as well as 3D acceleration when paired with the Nouveau Gallium3D "NVC0" driver. The accelerated support though has required manually extracting the graphics processor's microcode after the GPU was initialized by the proprietary driver. With the Linux 3.1 kernel, Nouveau can generate its own "FUC" microcode to circumvent this problem. In other words, there is now "out of the box" open-source support for NVIDIA GeForce 400/500 graphics cards.

  Nouveau GeForce 400/500 Fermi On Linux 3.1