A 14-Way Comparison Of NVIDIA vs. Nouveau Drivers

GeForce GTX 460: Finally onto the current-generation NVIDIA hardware... Fermi. The GeForce 400 Fermi GPUs launched last year as the first major architectural overhaul since the GeForce 8 (G80) series. Like the other generations of NVIDIA GPUs, there was good binary driver support from the start. There is effectively feature and performance parity between the binary Linux and Windows drivers, thanks in part due to the shared code-base between the officially supported operating systems by NVIDIA Corp. The only big feature exception in the Fermi Linux support is the lack of overclocking support. It is not a high priority for NVIDIA engineers to support Fermi overclocking since it is only an enthusiast-oriented feature and that with the Fermi architecture (and future generations of NVIDIA GPUs), it is much more complicated.

Due to the architectural overhaul, it took a while before the NVIDIA Fermi GPUs were reverse-engineered and supported by the Nouveau driver. Kernel mode-setting support was around at first without any acceleration support, and then later on came 2D/3D acceleration to the Nouveau DRM and Gallium3D components. Another limitation was at first these Fermi GPUs could not have accelerated support without loading the "FUC" microcode, which had to be extracted after first initializing the GPU with the NVIDIA binary driver and then running a few commands. This was only addressed in the Linux 3.1 kernel where the Nouveau DRM no longer requires the external FUC microcode but is able to generate the controller code internally. As a result, Nouveau Fermi 3D support is still relatively recent for end-users. The very latest Fermi hardware also requires the not-yet-released Linux 3.2 kernel for mode-setting support.

Another limitation of the Nouveau Fermi support is the lack of mainline re-clocking support yet, which can leave the NVIDIA GPU stuck in an under-performing state with lower clock speeds unless first loading the NVIDIA binary driver each time to ramp up the core/shader/memory clocks and then getting the Nouveau driver loaded. In other words, the Nouveau Fermi performance "out of the box" can be rather disappointing for some GPUs.

The Palit GeForce GTX 460 was bought and sent over by NVIDIA's Andy Ritger, the lead of their Linux/Unix driver team. The GeForce GTX 460 launched in July of 2010 on the "GF104" core. The GF104 core is clocked at 675MHz with 3.6GHz GDDR5 memory. The Palit GTX 460 had 1GB of GDDR5 video memory, a modestly sized heatsink, and requires one 6-pin PCI Express power connection.