There is likely more to the story than the 100 mhz of extra boost. I'm guessing the all core boost is significantly lower on the 3700x than the 3800x. It looks a lot like the 2700 vs 2700x. All core boost is much higher on the 2700x under full load than the 2700. I think its 3.5 vs 4 ghz at stock if I remember correctly. The 2700's stated boost is only 200 mhz lower than 2700x and has a 40w TDP difference.the 3800X requires ~40W more for 100MHz extra boost over the 3700X based on officially announced specs.