it's not just the payment coin it's the idea of buying a card especially for mining ,it wouldn't surprise me if amd or nvidia are paying this company under the table. no one knows what's the real Purpose of the mining if any, maybe it's all about selling the cards...:kookoo:
the Core i7-7740X and i5-7640X aren't so "cost effective" as the leaks suggested a few weeks ago combined with the added price of the x299 motherboard ,not that attractive.
your price range is very close to what it should be,this is the reason why intel will not lose much market share simply because the current prices of amd are not tempting for r3 and 8 threaded r5.