The 3930K is only supposed to turbo to 3.5GHz when all cores are in use.
Some motherboard makers have their boards use the max default turbo multiplier across all cores for better performance, and better looking benchmarks in reviews. This is usually perfectly stable, but is not strictly to spec. This has been referred to as Multi-core Ehancement.
Here is an article on the topic of: http://www.anandtech.com/show/6214/multicore-enhancement-the-debate-about-free-mhz
Some motherboard makers have their boards use the max default turbo multiplier across all cores for better performance, and better looking benchmarks in reviews. This is usually perfectly stable, but is not strictly to spec. This has been referred to as Multi-core Ehancement.
Here is an article on the topic of: http://www.anandtech.com/show/6214/multicore-enhancement-the-debate-about-free-mhz
