Intel Iris Pro 6200 Graphics Are A Dream Come True For Open-Source Linux Fans
The Intel Iris Pro Graphics 6200 (GT3e) as the fastest Broadwell GPU boasting an eDRAM cache and 48 execution units is a dream for open-source fans. Backed by a fully open-source Linux graphics driver, the Iris Pro Graphics 6200 found on the socketed Core i7 5775C is a dream come true that can compete with mid-range Radeon graphics cards on their open-source driver.
I've been testing the Intel Core i7 5775C processor on Linux the past few weeks. While I ran into some issues, after the third motherboard and switching over to Fedora Linux, the Broadwell experience has been great. Fedora 22 is running great on this high-end Broadwell desktop CPU.
Now with things running well, I compared the Iris 6200 Pro graphics to a few discrete graphics cards... The full i7-5775C Linux review is just a few days away, but as sort of a teaser, here are results for the GT3e graphics against some NVIDIA/AMD graphics cards. The Iris Pro 6200 graphics on the i7-5775C have a maximum frequency of 1.15GHz, support 4K@60Hz via DisplayPort, can drive three displays at once, boast 48 execution units, and support OpenGL 4.3.
All testing was done with the open-source drivers. Fedora 22 x86_64 was installed with all available stable updates as of this week. The F22 updated stack yielded the Linux 4.0.7 kernel, Mesa 10.6.1, and GNOME Shell 3.16.3. Tested on this stack was the Iris Pro 6200 graphics and then on the AMD side were the Radeon HD 6570 and HD 6770 graphics cards on the mature R600g driver as reputable mid-range hardware within my possesion. For Nouveau coverage there was the GeForce GTX 650, which is the only NVIDIA graphics card in my possession that is able to fully re-clock to its highest performance state (0f) under the open-source driver. There isn't any Maxwell re-clocking support for the GTX 750 on Nouveau right now nor is there any open-source hardware acceleration yet for the GTX 900 series, so those newer graphics cards couldn't be tested for this explicitly open-source comparison.
Besides having a fully open-source OpenGL driver stack, there is also OpenCL compute support for Broadwell via the Beignet project, but those tests are being saved for a later article on Phoronix. While the Broadwell GT3e is capable of OpenGL 4.3, right now only OpenGL 3.3 is supported by the Intel Linux driver though OpenGL 4.0~4.2 is coming close in a future Mesa update. All of these benchmarks were run in a fully-automated manner via the open-source Phoronix Test Suite benchmarking software.