Quote from: Epoch on October 19, 2012, 06:16:32 PM

Quote from: gmaxwell on October 19, 2012, 05:48:40 PM

Quote from: Luke-Jr on October 19, 2012, 05:26:52 PM

No, just your assumptions on difficulty. I don't expect any of these 60 GH range ASIC products to make even $1000 in 2013 alone. By design, difficulty will always bring the cost-to-mine very close to power costs. When it catches up, power costs will be all that matters. Until then, delivery dates before it adjusts are the key importance.

Agreed.

The people who have the view that the power doesn't matter only have it because they have high profitability expectations. The people saying that power is all that matters are expecting very long payoff horizons due to difficulty increases. I think the latter view is safer and also more correct, especially if you're not counting on being very early in your deployment.

Which I think results is another interesting bit to take away from the discussion: BFL is apparently not expecting their customers purchases to pay for themselves for quite a long time. This is fine by me, as it's also what I expect an I mine for fun and to support Bitcoin... but if you were thinking otherwise you might want to carefully review your expectations.

Although I generally try to take a conservative approach, in this particular case I would tend more towards the former idea: that power is not likely to play a significant role immediately (or more accurately, it is only PART of the equation). Rather, it is the ROI - Return On Investment - that matters. ROI takes into account both net income (from mining) and expenses (capital cost and running cost).

Consider this: I a purchased a mining device 6 months ago for $600 that generates $3/day and costs $0.25/day to operate. Assuming these numbers don't change over time, I can expect an ROI of about 220 days. Not bad.

Now consider a hypothetical device identical to the one above, except that it uses TWICE the power. Thus costing me $0.50/day to operate. Now instead of an ROI of 220 days I can expect an ROI of 240 days. A 10% increase. Is this significant? I would argue that it is not; there is little difference between 220 days and 240 days. Both are equally reasonable.

Let's take this further: if my running costs (electricity) ever became a SIGNIFICANT percentage of the mining income, I would stop mining altogether. I imagine many other miners would as well. For instance, back to my original device making $3/day and costing $0.25/day to operate : if difficulty went up so high to reduce my mining income to, say, $1/day, I would be unlikely to purchase another one. The ROI at that point would become too long (800 days) and it would not be worth buying such a device. Especially in an unstable and risky ecosystem as bitcoin.

So I don't believe that difficulty will ever rise to a level where running costs become a very significant percentage of the gross income; the ROI would simply become too long and many people would stop mining (or, perhaps more pragmatically, people would become increasingly unlikely to invest in new mining hardware, thus capping difficulty).

In this case, the first ASIC manufacturer to diversify into different cyrptocurrencies would have the edge in second and third gen mining devices.