So 128GB modules exist and available http://www.memory4less.com/crucial-128gb-ddr4-pc19200-m386aa... but at least 30% more expensive than 2*64GB: http://www.memory4less.com/samsung-64gb-ddr4-pc17000-m386a8k... and of course this is the cheapest vendor. Brand names will fleece http://www.memory4less.com/hp-128gb-ddr4-pc19200-809208-b21 you for 128GB modules while http://www.memory4less.com/hp-64gb-ddr4-pc17000-726724-b21 64GB is just a little more expensive.