Bitcoin Forum

Is it more profitable to join a pool or go solo? I'm running an HD 6850.

Also, what is the ETA at that speed running solo?

The expected generation output, at 170000 Khps, given current difficulty of 76193.9710474 , is 2.24415163496 BTC per day and 0.0935063181234 BTC per hour.

You need at least 2 GH/s to mine solo. Many people will not agree about this, but that's my opinion.

The average time to generate a block at 170000 Khps, given current difficulty of 76193.9710474 , is 3 weeks, 1 day, 6 hours, 43 minutes, and 23 seconds, which is much longer that average difficulty adjustment interval, so you probably won't find a block until next step. Well, next step will be lower than current, but this is not the usual behavior.

Welcome to my pool at deepbit.net (http://deepbit.net) :)

I would put more like 0.5~1 GH to mine solo... ie: minimum a 5970

Even with 2 GH/s there is a chance to get stuck with "unlucky" block for a month or two...

That's fairly irrelevant. Your expected payout from going solo is always higher. If you start mining solo with a CPU doing 1MH/s you will probably never find a block, but that is balanced by the fact that if you do, you'll receive a reward many times what you would have gotten in a pool.

Of course, mining solo increases your variance. Whether this is acceptable is mostly a matter of being able to cope with it emotionally. As you can see in the bitcoin generation calculator (http://www.alloscomp.com/bitcoin/calculator.php), with your rate you'll average 22 days per block but it could plausibly take 2 months (at current difficulty).

I agree with nster about the 0.5~1 GH/s suggestion, though you need to make sure you know exactly what you're getting in to.

Sure. A chance of 0.000011%.

Thanks, I'm liking your pool so far. I will keep mining in it.

I've known about bitcoin for a while but just gave it a try today, it's a very interesting currency and  I think it has a lot of potential.

Only for that day. On average it would be exactly the same, but with each difficulty step your chance will get lower.

Not quite. Yesterday there was a 524205-shares block in slush's pool and 489991-shares block in my pool two days ago, so it's really NOT that impropable. ~200-300k blocks happen even more often.

Yes. And your payout from the pool will also get lower.

It really is that improbable, because I've made a *gasp* calculation ( exp(-720/45) ). Meanwhile, the probability that a block is 520000 shares is 0.1%, so I'm not that surprised there was one in a pool that generates dozens a day.

You still get the part that was for days with lower difficulty.
Of course it's not a strong boundary, but i think that mining with ETA longer that difficulty steps is not funny enough - waiting for days and weeks without any result.

Oh, my mistake, was still thinking about 170 Mh/s.
When i started mining at ~22k difficulty with 900 MH/s, i didn't get a block for more than two weeks. Luckily i was mining in a pool :)

In THEORY you can get bitcoins A BLOCK OF 50 COINS by mining solo with just -0.5 ~ 1 Ghash/s.
But the question is when?

Haven't you seen BTCmine & bitcoinpool.
Even though they mine at not 1, but 4-5 Ghash/s, its very very difficult for them to get a block.

You can even control this entire universe with just a hair, but in theory only, NEVER in practical.
Statistics is to say you can win, but to win practically you have to run with LUCK.

They get a block every day at least on most days... That isn't too bad

at ~900Mh/s you get a block every 4 days or so on average, almost 2 per week and about 4 per difficulty change...

Am I the only who thinks that if you think it's not worth mining solo, it's not worth mining at all?  50 BTC is not a fortune and if you cannot get it in reasonable time, it's probably not worth bothering anyway. Pools are great if you want to get some initial small amount of bitcoins fast but in long term, it's too boring. Start with a pool, get some bitcoins and then mine solo. You can at least have some thrills like in lottery (which Bitcoin mining is).

My dual 5870 rig runs at 678 mhps. That's supposed to be a block every 5 days. But it's not unusual to get 2 blocks a day from time to time.

So I'd say anything around 500 mhps is plenty fine for solo mining. Getting some jackpots feels really good.

And one out of every 20 blocks should take you (at the current difficulty) nearly 17 days. And one out of 100 blocks might take you nearly 34 days. Assuming that the difficulty doesn't rise significantly during that time period.

As per you said 50 coins , if lucky , can get in 4 days at ~900Mh/s.
I am currently getting at least 3 coin per day at 275 Mh/s running 20 hours a day, coz of power cuts.
so for 4 days 12 coins at my speed.
275*3.5=~950
12*3.5=42.

so, in pool i am SURE, i MUST get 42 coins at least if i run at ~950Mh/s in 3.5 days.

I'm going to assume that you have bills and such to pay once a month--most notably the electric bill for running your beast of a GPU all day and night. You can handle some variance as long as you hit at least one block a month.

Here's the general formula: if your expected average time in days to generate a block is t, then the probability you'll go a whole month without generating a block is e^-(30.4/t) [(iven that there are on average 30.4 days in a year).

At 170 Mhash/s, at the current difficulty, your expected average time to generate a block is close to 22.3 days. So the probabilty that you go a month without is e^-(30.4/22.3), or around 0.256. That is, there's a somewhat better than 25% chance in any month that you'll come up empty. (In reality your miner will not be up 24/7 and the probability will be slightly higher.)

It's up to you whether the ~25% chance is worth taking. If you can self-insure for a month, you should be fine. Once you get rolling, you should set aside maybe 10 BTC per block for a rainy day.

I mostly use pooled mining because I'm new to the whole thing and still in the red. As I get more confident, I'll probably spend more resources on solo mining (unless of course the difficulty jumps up too high to be worth continuing).