There is almost no point for him to get the 5930k over the 5820k especially while it's almost $200 more expensive, unless of course he needs the extra PCI-E lanes which with 2 980's he wont.
Plus why did you change the motherboard and RAM? You didn't even answer his original question...
Anyway, in regards to the OP while strictly gaming you won't be looking at that much of a performance improvement due to your 2700k still being a competent processor. You will however notice the difference of having 6 physical cores once you start to stream and multitask where most stutters you once might of had will be gone and your computer will feel generally more snappy and responsive.
Hard drives should also still be bootable although it's quite common for drivers from previous components to conflict with new hardware.