Definitely don't get a 3930K for gaming..It's a complete waste of money! No games use 6 cores... The 3770k will match or beat the performance of a 3930k... Considering its a 77w part against a 130w, the 3770k is a MUCH better choice for gaming, seriously...
Here is a benchmark comparison:http://www.anandtech.com/bench/Product/551?vs=552
You'll notice the 3770k beats the 3930k in games, and only loses by a small amount in heavily multi-threaded synthetic benchmarks that use the extra 2 cores of the 3930k..
Just go with the build you listed in your first post, just with a 3770k!