Where did you get the $5k price on 28nm wafers?
Experience and industry contacts
edit, found a public source for you:
TSMC decided to increase prices for 28nm chips "by somewhere between 15% - 25%. Given that a wafer processed using latest process technologies can cost $4000 - $5000, ..http://www.xbitlabs.com/news/other/display/20110912192619_TSMC_Reportedly_Hikes_Pricing_on_28nm_Wafers_Due_to_Increased_Demand.htmlPlease note the date on that, 2011, when 28nm was brand new, very low volume and very few fabs offered it. 28nm is now mainstream, offered in volume by all major fabs. So If anything, $4000 today would be a high estimate, but Im okay using it since Cointerra is not an AMD or nViida and pretty low volume for a company like TSMC.
Does that 5K include the design cost of the masks?
Absolutely not. Masksets, especially for 28nm, are orders of magnitude more expensive, but its a one time, sunk cost. Once you have a maskset, to determine production volume all that matters is the variable production cost vs market value. Sunk costs will determine whether or not you end up making a profit, but not whether or not you should produce more batches. Its like when buying a miner, once you bought it, purchase price (sunk cost) no longer matters to decide to run it or not, you will run it until it earns you less than it costs in electricity, but the purchase price will largely determine if you end up making a profit or not.
What about the bumping and binning processes? The boards? Etc?
"Bumping and binning" is part of testing and packaging. Its not included in the $5K/wafer price, but it is included in a 'a few dollar per chip", since the cost is typically closer related to the number of die's than wafers.
If you want a public reference for that too, this is all I can find quickly:
http://electroiq.com/blog/articles/2001/03/technology-comparisons-and-the-economics-of-flip-chip-packaging/(scroll down to the last charts as the others are unreadable, and you may want to note the numbers they picked for average die cost too: $5. Not $50 much less $500).
Please note that article is more than 10 years old. Gives you an idea what BGA packaging costed back then, when it was state of the art technology. The numbers have dropped since, but are still within the same ballpark of a few dollar per chip.
For PCBs, you can get an idea from the prices of infinitely more complicated PC motherboards (that contain dozens of other asics) and still sell for $20 or so in bulk, or from a raspberry Pi that retails for $40 including the SoC, RAM, IO etc.
PCB cost doesnt amount to much in the big picture.
Sorry, I just don't see it.
You can lead a horse to water...
Hmm, let's take a look at avalon with your numbers. We know Avalon produced 3 batches of product and took orders for 1,000,000 chips. I can't seem to get a solid number, but 400MH per chip seems likely. So, we have 1500 units operating at ~65GH which gives up ~164 chips per unit. All in all that comes to 1,246,000 chips. At 1188 chips per wafer, that cones to ~1050 wafers. Those 1050 wafers would run ~$4.2M at $4k each or ~$5.2M with the masks. $4.17 per chip or $684 per unit. $1299/75btc/75btc = $389,700/45kbtc/45kbtc = $911,700/$3,476,250. $4,777,650 income from the 3 batches. 78000 BTC = ~$10,920,000 for the 1,000,000 chips. $15,697,650... I can see Avalon taking a 3x markup overall, even though it was mostly B3 that got screwed.
BFL went with 65NM and seems to have ~4GH per chip. They must have a bigger chip size or did a better job with the traces, as halving the technology size should only give a 4x increase in traces. Going to 28NM would roughly involve another 4x increase in traces. 6.4GHz off of a ~4.65x4.65mm chip (16.13mm
2). A single 500GH chip would require nearly 78x as many traces, or 35.5mmx35.5mm which wuld rival the size of an Intel processor which is 37.5x37.5, in which case using a 300MM wafer you'd get 48 chips. At $4k per wafer, that's $83.33 per chip.