Quote from: Kuschelweich on July 28, 2013, 04:20:06 AM

Quote from: dree12 on July 28, 2013, 03:33:52 AM

Quote from: Kuschelweich on July 28, 2013, 03:11:19 AM

Good job keeping up with the current hardware prices. Erupters and K1 nano already have their price drops reflected.

My only concern is the profitability calculations I'm getting for 5 K1 nanos are very different from the BitcoinX calculator. Specifically it's saying I'll never make my money back, and actually lose 80 bucks. Where as the other one says I'll at least make some profit. I didn't mess with the difficulty increase predictions on either, as I'm a noob in that regard.

I have both the calculators set up with exactly the same info, except bitcoinx measures difficulty increase different(Profitability decline as a decimal). I also removed any hardware costs to make sure they start with the same total hardware cost. For some reason the difficulty is defaulting to 26M, so I changed it to 31.26M to mirror what bitcoinx has.

This is the info I entered:

5 x K1 nano @ $275(250 + 25 shipping)
Same 10W power @ .12kw/h cost
1.75GH/s | 1775MH/s Hash Rate(Assuming an overclock @350MH/s)

Here's where things get interesting. According to this calculator, in 6 months I'll still be about $80 in the hole. Where as bitcoinX says I'd have made 152 bucks, with the hardware paying itself off roughly at the end of month 3. I'm a bit confused because one says I'll spend more than I'll ever make, while the other says I'd make an okay profit.

Not sure which I should believe? Huh

There is a default $100 allocated to shipping and PSU costs. Check to see if those are active. There is also a default pool fee of 2%. Try disabling that.

Finally, set BitcoinX's decline per year to 0.003. It defaults at an unreasonable 0.61.

Thank you for the help. I made sure Misc costs were 0, set shipping at the actual 25 for the correct 275 total, and set the pool fee at 0. Getting a $78 loss now.

I changed the profitability decline at BitcoinX to .003 and it's changed quite a bit. It now says $120 loss after 6 months and staring to lose money after that.

How is the decline represented in the bitcoinx calculator? I thought it was a percentage decrease in decimal form, but that doesn't seem to be the case.

Anyway so are these things indeed this bad of an investment? With how well they sell I figured there was at least a small profit margin to be made. Up until yesterday I've seen quite a few people buying them for nearly 1 BTC each Shocked

.

I did some messing with the numbers to see if I could make them profitable, and apparently at about $30 each at stock speeds I could make 20 bucks

. At their current price however even if you could overclock them to a very unlikely 450MH/s with liquid cooling you wouldn't see a return Sad

.

Thanks

Difficulty is going up by ~62% per month, so that's a 0.617 profitability after each month. BitcoinX measures in years, and populates the field with monthly data... it doesn't really make sense. So change the number to 0.617¹², which is ~0.0031.