So, finally I am back on this :-)
I have 5.1 euros per day for electricity (slightly less, but I rounded it up), I have 2269kH/s which nets me on average per 24h 17.8 euro/day with current ratings
Thanks a lot for the numbers - that is 7.84 euros/day/MH.
Very nice. I earned less. Much less.
And here is also the explanation for our different opinions.
You have been optimizing for a different region of the overall problem than me.
So we are both right, but in the two different realities "low / high earnings"
You need to compare earnings vs spendings and nothing more.
I know.
Profit is the only thing that counts.
Sounds a bit Ferengi, though :-)
But it's good that you insisted, thank you very much - now I see clearer as
I recalculated the whole thing, all the
numerical empirics is published here in #101.
I see all of you in this forum talking about kH/W, but that doesn't matter.
I think we should consider both.
Or put differently: For you not, but for me,
khash/Watt does matter.
The used electrical power P is very physical. I am talking efficiency.
Let's try to see clearer:
There is a "physical" or "hashing conversion ratio" h ~ H/P which makes hashrate H out of Watts P
and a "mining conversion ratio" m ~ C/H which makes coins C out of hashrate H, depending on pool choice & luck.
In the end, we get coins C from electricity E like this
And profit F (for Ferengi
) is coins C minus electricity E
F = C - E
= m*h*E - E
= (m*h -1) * E
Now we have a new proportionality, between profit F and electricity E, and the factor is (m*h-1)
Our profitability limit is at m*h == 1. Below 1 means paying more for electricity than earning in coins.
Personally, I would really like to see much more F coming out than energy E put in, so
- but that's my personal taste.
Look at an extreme case:
Even with m*h = 1.1, you still make profit - but me, I wouldn't want to anymore, because I cannot responsibly do that, put in 100 euros electricity to make 10 Euros profit.
Your m*h is 3.49, isn't it?
I have 5.1 euros per day for electricity ... which nets me on average per 24h
17.8 euro/day with current ratings (average over last 17 days ...)
(17.8-5.1)/5.1 = 2.49 That's cool. Very cool. Good m,
and good h, I guess.
We cannot really choose E freely - just in jumps of buying more cards :-)
Within one card, E is simply proportional to P
... which is a nontrivial function of (CC, MC, VDDC),
and P and H are interdependent.
And what can we say about the absolute hashrate H? Actually,
both H and P are nontrivial functions of our cgminer settings:
{H, P} = function (CC, MC, VDDC)
with h ~ H/P in khash/Watt my efficiency ratio
and H the absolute hashrate in khash/s
Ideally we would actually like to optimize efficiency h
AND the absolute hashrate H, right?
At your highly successful m ~ 7.84 euros/day/MH, I can well understand that you rather want to push your H as high as possible, even if your P goes up even more, and thus your efficiency h = H/P decreases. With e.g. m ~ 5 Euros/day/MH, the situation already looks different. Real numbers are in
in #101.
Meaning when you lower your total hashrate 10% your total earnings will lower 10%.
True.
C ~ H
Then we can calculate differences in absolute earnings,
and differences in relative earnings (in relation to energy costs).
Let's optimize both; depending on the current m, different strategies might be profitable.
For every euro you earn less per day, you have to spend more than a euro less per day or it's less profitable.
And that's exactly where my thinking lead me to khash/Watt being the perfect measure to optimize.
On that way, I had lost track that I am also lowering my absolute earnings C if I lower my hashrate H, even if at the same time I succeed in increasing the efficiency h of the machine. And if I am in the high earnings realm, I actually loose profit.
I appreciate your reminder!I had always hoped that we together find another sweet spot (CC, MC, volt) with a higher absolute hashrate H, and still very good efficiency h = H/P but that hasn't happened (yet).
The search is still on, people - go and test your cards in unusual clock settings!If you want to please check my math. As I was swapping variables a bit to make it clearer, there might be a typo still.
And when you do your calculations, make sure you use TOTAL system power, because only your card's powerdraw is useless.
When you pay your bills, you have to pay for total powerdraw, not just your cards.
Sure.
I have added 40W, that's half of the baseline consumption, because I have two cards in there.
For 4 or even 6 cards, it's slightly better, of course.
So lowering powerdraw by 25% for every 10% hashpower lost means lowering total power draw by 25%.
I understood you ... but have a look at the numerics in posting
#101 and #102 please.
Enough theory, we want to see numbers now!
