AMD Radeon HD7870XT (CGN1 - This architecture has been dropped for 2.79)
Broken: daily builds in general. current [blender-2.79-ef8bbc8] but also earlier versions, e.g. [blender-2.79-2bf3825]
Worked: Any release Install of Blender.
Short description of error
Switching to the Rendertab crashes Blender daily builds.
Accessing the [System] Tab in [Blender User Preferences] does too.
All thirdparty addons disabled.
When disabling the Cycles Renderer via [AddOns], aforementioned panels are accessible again.
Please note that my GPU architecture has been dropped for 2.79 - this might cause the crash.
Still it works for the release version and should ideally do so for daily builds.
Exact steps for others to reproduce the error
Just open Blender - empty scene - and switch to the Rendertab while having Cycles Renderer enabled.