Here's a comparison of the Ubuntu 12.04 LTS versus Microsoft Windows 7 performance when it comes to using Intel Sandy Bridge and Ivy Bridge processors with integrated graphics. While the Sandy Bridge graphics performance was once faster when it came to OpenGL with the open-source Linux driver, that's no longer the case. The Linux OpenGL performance for both Sandy Bridge and Ivy Bridge hardware is now slower in most GL workloads than Intel's Windows 7 x64 driver.
In February of 2011, one month after the Intel "Sandy Bridge" processors began to ship, I ran some tests that yielded results showing Intel graphics on Linux were still behind Windows. However, the Intel Open-Source Technology Center developers responsible for the Intel Linux graphics stack were aggressive in optimizations and bettering the Sandy Bridge Linux support. By May of last year, the Sandy Bridge Linux driver could out run the Windows driver. Since last May, the open-source Intel Linux driver developers have continued making optimizations when it comes to bettering the OpenGL support level within Mesa and implementing new SNB+ functionality, performance enhancements within the Intel DRM (Direct Rendering Manager) Linux kernel driver (RC6, etc), and the bit of work still left within the xf86-video-intel DDX driver. At the same time though, the Intel Windows developers working on their closed-source driver have been improving their support and performance too.
With the recent launch of the Intel Ivy Bridge processors having the new Intel HD 4000 graphics, I found it time to do another Linux vs. Windows comparison for Intel graphics. Intel HD 3000 graphics (via the Intel Core i5 2500K Sandy Bridge) and Intel HD 4000 graphics (via the Intel Core i7 3770K Ivy Bridge) were tested with Ubuntu 12.04 LTS x86_64 and Microsoft Windows 7 Professional x64.
The hardware was maintained throughout testing between both operating systems, aside from swapping out the Core i5 2500K and Core i7 3770K processors on the ECS Z77H2-A2X motherboard.