Doom 3 and Quake 4 are still benchmarked at Phoronix since id Software provided quality Linux ports of these id Tech 4 titles and they happen to run well now on the open-source Mesa/Gallium3D graphics drivers. It was with these id Tech 4 games where my initial Haswell Linux OpenGL concerns appeared... While Haswell is all about increasing power efficiency and graphics performance, for Doom 3 and Quake 4 the HD Graphics 4600 performance was disappointing. When using the same hardware (aside from the CPU/motherboard) and same software across all of the test configurations, the Core i7 4770K was actually slower than the Core i7 3770K "Ivy Bridge" with HD 4000 graphics. For Doom 3, the i7-3770K was 15% faster and for Quake 4 it was about 18% faster... At least the i7-4770K was better than Sandy Bridge and the lower-end HD 2500 Ivy Bridge. This is clearly a driver issue on the Linux side and hopefully will be worked out soon enough. For the AMD 10-5800K Trinity system, Haswell was much faster when it was an open-source driver comparison, but it will be interesting to see the Catalyst driver performance when tested in the upcoming discrete GPU comparison.
At least for Unigine Sanctuary, the HD Graphics 4600 from the i7-4770K are running much stronger than the i7-3770K. The Haswell CPU is about 16% faster than the previous-generation Ivy Bridge.