Link to your source please?
One can easily estimate the cost.
First , low perfs low core count CPUs are used ,
the ones with smaller die surfaces...
Low frequency memory , also cheap to produce.
Low consumption means lighter , hence cheaper , batteries
as well as power supply requirements being less demanding ,
allowing use of lower current , read cheaper , devices and
overall circuitry...
Less materials are used , that is cost/kg is way lower.
Only an eventual SSD is a big cost.
Overall , ultrabooks are just a try to sell at hefty prices products that
are cheaper to produce but still with little offerings , as are the
tablets that sell for prices with no relation with real costs , hence
intel s trying to create such an irrationnaly overvalued product.
Wait a few months , the bubble will burst , as either ultrabooks
get way cheaper or the concept will collapse due to consumers
unwilling to pay more than about 500$...