Topic: The last month is among us.. - page 4. (Read 12169 times)

Damn, and I just got my brand new 7950...although I got it for gaming.  I only do mining on the side when I don't use my computer.
Gets me about $50 extra a month....yay 

Keep in mind that prices change on availability and demand... with only half the output and 10x the difficulty I would expect prices rise at minimum 250% within 1-2 months! The price will most likely drop a lot immediately after the split because of all the GPU miners selling their BTC right away if they quit but will then level out...

Or you could look into ASIC alternatives like the business my colleagues and I have started! We're offering ASIC Mining Contracts at as low as 0.25 BTC that give you the full proportionate power of an ASIC without having to purchase one individually. That's nearly 125MH per contract and no worries of power! With careful reinvestment you'll have over 1GH after a year, not bad for .25BTC IMO...

Either way I recommend holding off selling your BTC and your GPUs for a while! If you'd like to see our ASIC Mining Contracts you can check out the details at our website. We are going to keep everything 100% private and confidential because of all the people that got screwed by GLBSE!

If you're interested:

Progressive Mining Contracts
http://www.progressivebtcmining.com/

Have you had any hardware failures from the hardware you started with then?

Actually, that set of calculations was made on the assumption of 25BTC block reward. With a 50BTC reward the return is better.
My mining cluster (15*5870, 4*5970, 1*6850) returns about 2.75BTC/day (about £21) for a power cost of about £10/day.
Not a huge pile of cash by any means, but... about £70/week and about 2kW of useful heat contributed to heating the house while I sit back and do nothing. I can live with that.
The hardware paid for itself long ago - I started mining in Nov 2010.

As variously pointed out, the best plan for GPU mining after the block reward drops to 25BTC depends on what you pay for power. Break-even mining is worth doing if you can use the heat. If you have night-time low cost power, push clock speeds up overnight and underclock/undervolt during the day. A mining rig with 3 5870s running at 0.95v gives about one and a half times the efficiency that it gives when running the 5870s at 1.1625v.

We will each have individual circumstances, and so each of us will have to find the right approach... which for some people will no doubt involve stopping mining, for others it might involve underclocking and undervolting. Others will order ASICs. I don't have any feel for what the value of BTC will be in a month or two. It would be nice if it doubles (I do have a few k BTC stashed in an offline wallet) but I am in no sense counting on this, thus the power measurements on underclocked GPUs.

I do not think that there will be any significant drop any time soon, if at all. If only difficulty is going to increase rather sharply (over the next 6 months I would think) once the ASIC start to be delivered.


I would be very surprised if anybody would currently be joining GPU mining. In fact overall network Hash/s rate has been very stable these past months and I would think that there is a lot of "wait & see" occurring right now. Most people are either waiting for their ASIC rigs to be delivered or keep mining before the halving and the ASIC tsunami before committing to ASIC or not. Anybody investing in GPU rigs today would most likely never amortized their investment unless you already have a rig and add few cards to beef up your system. Again, the overall network Hash/s rate indicate this is not the case.


I agree with you that this is very difficult to predict. However, there will be less BTC available, no matter what. Many people actually hoard their BTC when you look at the amount of daily exchange transactions being executed or simply use them for BTC-to-BTC transactions. In theory, price could double rather quickly following the halving. Let see what happen, this will be a very interesting time for bitcoin.

If you think solar power is free or cheap, think again: There's a reason why the german government subsidises solar power with something like €0.35/kwH. It might be a little better in places with a lot of sun, but I doubt you can produce for cheaper than what you pay (as a US-citizen) at the plug.

Also: running miners only when the sun shines is not making good use of hardware and still-low-difficulty.

I assure you: if it's not profitable to mine by buying elictricity, it is also not profitable to install photovoltaics for your miners.

I think it'll depend on whether or not the difficulty drops and by how much.  No matter how much the difficulty drops though I think those who didn't pay attention to efficiency (dropping mem clock speed, getting many cards into one motherboard, etc..) will have a hard time turning a profit.  I think this because I don't see how there is going to be a spike in BTC value vs other currencies just because the rewards are halved.  It isn't like the overall number of bitcoins dropped, just the rate they are being introduced into the economy so it isn't like each one became more valuable for any particular reason.

This is assuming that BTC value would not increase following the halving. It is possible but I would doubt this will be the case. In the end, profit is exclusively based on the BTC value versus other currencies. It is very possible that GPU miners will actually be able to make a nice profit prior to the ASIC arrival while the difficulty is still low and the BTC price increases, offsetting the reduction in BTC reward.

Let see, the next few months will be interesting in this regards.

just countin down the days :/

And that is with 50 BTC per block reward subsidy.  So the drop to 25 BTC will in an instant make mining on GPU something you can no longer do at a profit, regardless of whether your rates are daytime or nighttime, right?

I plan on keeping my quad 7970s for password cracking gaming and gaming. Or maybe I will sell two of them.. hmm..

Something a lot of people don't understand is that MHs/W does NOT = the most profit. If you doubled your power usage, but tripled your BTC earned per day, I bet it would be more profitable on a per day basis.

That is pretty high electric during the day tho. I think you're on the right track: undervolt during the day, and overclock during the night.

Hmmm... I am in the UK where power costs about £0.13 by day and £0.065 by night (7 hours out of 24)

A machine with 3 underclocked, undervolted 5970s was measured to use about 300W at the wall socket. It produced about 820MH/s.

Assuming that the difficulty doesn't change from now to block 210000 (questionable) we have:

 In 17 hours, we use 5.1kWh, costing £0.663.
 In 7 hours, we use 2.1kWh, costing £0.137.
 In 24 hours, we use 7.2kWh, costing £0.80.

 We make 0.125 Bitcoins per day, value about £0.97.

 So there is a profit there, just a very small one.

 Overnight, when the power is cheap, it is worth ruinning the 5970s at a higher voltage and clock.
 During the day, the profit is tiny, but worth keeping the machines running as it is winter - the heat has value.

http://bitcoinx.com/profit/ is also a good one.

https://bitclockers.com/calc

I wonder, with GPU's dropping off because of reward halving, if diff will substantially decrease till ASIC's make their way in. If thats the case, imagine if diff fell by 30% or more... rofl, then we'd see more gpu's coming back online till ASIC. It will be interesting to watch!

Anyone know of any calculators that allow you to change out the BTC payout rate?

I wonder if .09 /kWh still makes money after 210,000.  Time to hit up some calculators.

Fancy that, I pay 65/75 :-). I haven't found a calculator that accurately emulates what I see pooling.

You would be in the extreme minority then.

What do you pay for electricity?

I ran the numbers and find that about $0.11 per kWh is breakeven on the most efficient GPU configurations.  So unless you are paying like $0.07 per kWh or less there's no point in GPU mining after block 210,000  (unless difficulty takes a dive from other GPU miners dropping out).