Last week I delivered benchmarks showing Mesa 9.1 delivers faster Intel OpenGL graphics. The benchmarks in that article were carried out on an Intel Core i7 "Ivy Bridge" system with HD 4000 graphics while since then there have been many requests to have similar tests done on a previous-generation Sandy Bridge system. As a result of those requests, here are benchmarks of an Intel Core i5 "Sandy Bridge" processor with Intel HD 3000 graphics as the Mesa 9.1 performance is compared to the earlier 9.0.2, 8.0.5, and 7.11.2 branches.
This Mesa 9.1-devel Sandy Bridge benchmarking was done just like the aforementioned Ivy Bridge benchmarks as well as the Mesa 9.1 Radeon Gallium3D benchmarks. There was also the Intel Linux 3.2 to 3.8 DRM comparison for the kernel-side of Intel's open-source Linux graphics stack.
An Ubuntu 13.04 development snapshot was installed onto an Intel Core i5 Sandy Bridge laptop reference development platform (HP EliteBook) with an Intel Core i5 2520M processor bearing Intel HD 3000 graphics. The Linux 3.8 kernel was in use on the system with the xf86-video-intel 2.20.19 DDX while the Mesa versions were built from source and compared going back to Mesa 7.11.
The Mesa source-code was obtained from the various Git branches and came down to 7.11.2 git-1bdf31e, 8.0.5 git-a8ff9a4, 9.0.2 git-0f687f8, and 9.1-devel git-4bdf545.