Bitcoin Forum

Hi All,
I am currently mining >7500 MH/s (on a pool) and would like to know if this kind of setup is better solo or with certain pools. I plan on expanding this to >10000MH/s by the end of next week.
Thank You,
Paul

you'll average a block every 29 hours.

why on earth wouldn't you mine solo?

sure. "only" ~50 bigger farm and you can get serious Hardware utilisation, finally.

Holy christ what kind of hardware you have dude?

If you really have 7.5Ghash/sec there's little point to being in a public pool.

If you mistyped, and have 7.5Mhash/sec, then you shouldn't be mining at all.

Nope. 2**32*244139/7567e6/3600 = a block every ~38 hours.

< shrug >

if the (old) Bitcoin Calculator is wrong, then it's wrong.  but that's what it says for 10 Gh/s.

Hi I'm new to bitcoin and have many things to learn, may I know how you guys come up with these figures ? I'll soon be expanding my mining capacity too and would like to know at which point in the future should I consider mining solo and why.

try these two:

http://www.alloscomp.com/bitcoin/old_calculator.php
https://en.bitcoin.it/wiki/Mining_hardware_comparison

but mostly, just read the mining sub-forum.  every day.  over and over...

We are both right. I quoted numbers for 7567 Mh/s. For 10 Gh/s it is indeed ~29 hours.

ah, of course.  sorry - my mind was busy being boggled by the idea of 10Gh/s in my living room...

By definition, at difficulty 1 you must hash an average of ~4 billion blocks (exactly 2**32) to solve one.
So at the current difficulty of 244139, you have hash 2**32*244139 blocks. Just divide this by you hashing rate to find how long it would take to solve one.

No, it's really 7500MH/s. I am running 6x machines with 2x 6990s in each machine and I plan on expanding to 4 more machines next week. The hard part is keeping them cool enough - so I am moving them to a facility that has a good A/C and enough power (each machine takes ~10A @ 110V).

I will try solo mining since I am only at ~15BTC/24 hour period.

Thank You,
Paul

even minus 2% for slush's pool, with 7.5 Gh/s running pooled, you should be somewhere around 30BTC/day...

Hmm... I will need to recalc this then. Any difference between slush/deepbit/etc? I will need to run the system for another 24-48 hours to get a better baseline.

Thank You,
Paul

with 12 6990s, you should be getting about 9 Gh/s already - that's at 750 Mh/s each.

what are your boxes made out of?  OS, mining program, etc...

I am on BIOS position #2 (standard) due to heat concerns and crashing - so I am getting around 300MH/s per GPU (4 GPUs/PC * 6 = 7200MH/s). One of my machines is watercooled and I have that one set fairly high (~400MH/s). I am using an Asus Mboard w/ 2x PCIe, AMD Phenom x4, 1GB RAM, 32GB HDD, 1600W PSU, 2x XFX 6990s, and Windows 7 (64 bit). The water cooled PC is using Koolance blocks and reservoir and has a 4x PCIe MBoard (it will have 4x cards in it soon running Linux, waiting on other 2x cards for this one - the other 8 cards for are in the garage waiting to be assembled).

I am using GUIMINER since I needed something quick to test and play with.

Quick question - do you need the crossfire cable connected between the 2x cards? Any advantage to this vs not? (Going to bed soon - will check posts in morning)

Thank You,
Paul

Question - why does common concensus seem to be that he should go and mine solo wiht 7.5 Ghash/sec?

It's not like his volatility doesn't lessen a ton like most of the rest of us, and a even a 2% fee (there are several with lesser fees) isn't a huge cut. Why wouldn't he want to mine in a pool?

because the main reason to mine a pool is to even out variability.

with that kind of Gigahashage, he has no variability to speak of.

Wow... You have 12 6990's and only get 7.5ghash/s?? Holy crap dude, and they are overheating? And you're on a pool?
Seems like every day someone rushes headstrong into mining without thinking things through or fine tuning their operation.

My other observation around this forum is that a lot of people really don't know much about hardware, cooling, systems and that general area. Even the smartest bitcoiner may not be proficient in this area.I'd suggest browsing some PC forums to learn in this area. Overclock.net and xtremesystems are probably some of the better places. *Yes I know OCN is shit with the retarded ass moderators, BUT there is still a lot of information there by a lot of great MEMBERS (not moderators).

Even big pools like Slush's pool still experience variance. BTCGuild has grown rapidly to > 125 Ghash/sec and it still experiences rounds ranging from 11 seconds to 12 hours.

Why would a 7.5 Ghash/sec user not benefit from reducing his variance like the rest of us? He'll still experience a fair amount of variance?

@Clavulanic: I am running these stock with fan cooling only. I am expanding watercooling to all soon (the watercooled machine is 400MH/s per GPU and running around 60'C).  Stock (which mine are, except for 2x cards) are expected to be at 300Mh/s, so I do not understand why I should be way above 7.5GH/s.

If you have any suggestions on how to "fine tune" my operation - let me know. It is always easier to tell someone else to destroy their $800 card instead of your own :-)

Push cards higher...
Make more BTC...
Buy new cards if cards start getting destroyed...
Still would make more than running at those girly stock speeds...
Those cards built for 80C+...
I get almost 1/3 of your Mhash on my 3x 5970 setup...

Where to begin...  first Linux, I'd install it, phoenix, and use 2.4 SDK and phatz kernel.  I'd experiment with underclocking the memory on the card, you should be able to find a sweet spot, and at the same time reduce heat production (you don't need the memory speed for mining, by reducing it, you don't hurt anything on the card).

I would expect you should be able to get 8.4+ Gh/s without having to overclock the core.

Phatk and memory underclocking does 0 or negative differance on the 69xx gpus. do read up some before spitting out that.

I have 6950's running and did see a slight bump in using phatz (4 or 5 Mh/s), and underclocking the memory doesn't hurt performance in my experience and does seem to help reduce heat.  You notice I didn't state that he would see a Mh/s bump from reducing the memory clock, only that he should be able to find a sweet spot where it doesn't hurt Mh/s and does reduce heat.

linux, yes.

and take the MemClocks down, to reduce heat.  with AMD CC 11.5 and SDK 2.4 (required with 6xxx series cards for best performance), lowered MemClocks may not increase the M/h rate (might even lower it by a percent... OH NOES!), but it will dramatically reduce heat output.

try DiabloMiner - it's just as "quick to test and play with", if not quicker; and usually faster.

with linux, use AMDOverdriveCtrl for clocking - it's not as crazy powerful as some of the windows utilities, but it'll do; and you're much less likely to take the card past a point where you can damage it.

if you're really set on spending major dough to put water-cooling on all those machines, then do  it smart - get longer tubes, and use external (not case-mounted) radiators.  hang the radiator and fan bundle outside a window on brackets.  then you won't need to spend anywhere near as much on AC.

1: The Bitcoin network is much more robust if it is distributed as it was intended to be, instead of being centralized into several large pools.
 
2: Any fee is huge if you have that kind of mining capability, and it most definitely cuts into your bottom line. Paying a fee to avoid variance with that kind of hashing power would be like throwing money away. The day will come when only the most efficient miners can make a profit, and the ones that start maximizing their potential now will certainly stick around longer than those who don't.

Anyone saying he should go solo...
Probably never have studied statistics...
Or are just some degen gambler...

Go read up on Poisson distribution...
You be suprised how huge variance is...
He could mine for week++ with no blocks...
At this difficulty level...

Actually going solo...
Could break his operation...
Unless he is degen gambler...
3% for reduced variance is nothing here...

More importantly, there are pools out there with 0% or .5% fees...  It's worth the effort to use a pool even 8Gh/s.

If he mines 8.5=10 Gh/s his average for hitting a block is around 1.5 days. Going a full week or more without hitting a block would be statistically insane. If I had half speed I would go solo instantly.

As Vladamir said, the hardest part is not sitting there watching it every minute and worrying that it's not getting anything.

That is ridiculous to watercool all of your cards, with that money you could build several more rigs. Hell, it'd probably be cheaper to buy a window AC unit and blow that sucker at the systems. Though I will say watercooling would be a great way to have all of your heat exhaust outside of your house if you have any rigs in your house.

Anyways, the notion around this forum that overclocking will destroy your cards is also ridiculous, do some research, visit some forums and find out how it's done. There are correct ways and incorrect ways to approach overclocking your cards. There are also things that should be done to your cards. Reseat the heatsinks with better TIM, space them properly and have good airflow.

agreed.

i was solo when difficulty was 90 whatever.  when it hit 127,000, i put half my miners in a pool.  at 157,000, i put 'em all in a pool.  i'm running at 2.1 Gh/s right now.  if i get up over 5 Gh/s, i'll go solo again, as long as difficulty stays under 350k.

pool vs. solo is all about the temperament of the miner.  got patience?

vladimir is correct.

Why don't you invest all your life savings in mining...
It's because of the risk involved...
Risk comes from future BTC price...
Future difficulty levels...
And how you run at solving blocks...

Reduce one of these risks...
And you can invest more...
Pay 3% to reduce varience...
Will make you be able to invest more...

Your risk adjusted profit will be better...
Thats where it all is...
You guys should study maths/economics...
Unless he is very willing to take risk...
For all his life savings...
It would be crazy going solo...

Even with 10Ghs at this difficulty level...
If he finds block every 1.5 days...
He still has 1% of going week without block...
Hardly statistically insane...
Poisson process, something every miner should know...

I think we have the mother of all "..." syndromes in here  :o

I was thinking about this, can someone answer..

Even if he has 7.5Gh total, each card is still only giving him 600Mh. Since not all the cards are working on the same block, wouldn't it actually take something like 20 days (according to the calculator) to solve like 24 blocks? Instead of one a day. In reality, each core of each card is still working by itself on a block right..?

... o_0

um, no. Each GPU gets it's own work and they all work toward solving the current block.

If a 100 GH/s pool has variance people moan about, a solo miner is going to get even worse variance. Solo if you want the chance of getting more bitcoins, but accept the fact that there is an equal chance you'll get less.

The average number of bitcoins you get in a pool is similar to the number you get solo. The only real difference is the variance and any fees.