I was discluding cost of memory chips, sorry for the confusion.
But the fact that a 256MB DDR500 costs well over $100 has no impact on how much ATi or nVidia pays for them.
Firstly there is PCB and other physical parts cost in there that ATi and nVidia don't pay, they don't pay the cost to put the chips onto the PCBs either, and there is all kinds of other costs that knock the price of that memory up just like they do for video cards.
My 10s of dollars number was discluding memory cost though, sorry I didn't make the clearer.
And yes margins are a lot slimmer than that, but the fab cost is only a tiny portion of the final cost of the card.
There are R&D costs, marketting costs, employee wages, distribution costs, capital equipment costs. And the final price you see on retail shevles isn't what ATi or nVidia sell them to the wholesalers for anyways, you have several steps before they get to store shelves, and every step adds a % for profit for that person.
None of that has any effect on how much it costs to physical create the card, but they all heavily influence final price.