Topic: Consolidated Litecoin Mining Guide for 5xxx, 6xxx, and 7xxx GPUs - page 13. (Read 624202 times)

Do the 1GB, 2GB, and 3GB models affect KH/s? I'm not sure if I should spend more money on the cards with more RAM unless it adds to performance.

I agree, everything I have read suggests the Gigabytes (7950 and 7970) are great LTC miners. Only problem is they are voltage locked so if you live in a country with high electricity prices they might not be the most efficient.

If you want a MUCH better value, get this:

http://www.newegg.com/Product/Product.aspx?Item=N82E16814125414

I have 2 of those.. and 1 of the 7970 sapphire dual-x.

the 7970 gets 690khash..

each 7950 ($100 cheaper) gets 670+khash

paperkat,

I have two of the Sapphire Dual-X.
See my quote above for settings.
At those settings I am running 1.025 volts which saves a surprising amount of power.

Placing a order for my first 7970 on monday:)

SAPPHIRE RADEON HD7970 DUAL-X 3GB, thats the one i should get, right? Been reeding in this thread, seems like khash/s is pretty poor on those factory overclocked Ghz editions.

A share is a proof that your mining software is working hard and working correctly.  It's the same thing as submitting a solved block to the bitcoin/litecoin network, but it's done with a lower difficulty setting.  This means your mining software can send frequent shares to the pool server, and the pool server can check they're valid and tell how hard and effective your miner is.  If any of your shares are actually strong enough that they do solve the block then the pool server passes them on to the network and usually collects the reward itself, then distributes it to the miners according to share levels, by various algorithms.

I find the dice metaphor really useful.  Imagine Max and Megan are rolling 100-sided dice, and Naomi will pay them $10 every time they roll a 1.  That's pretty boring, it could take a long - and variable - amount of time to get any money.  So Peter sits between them and Naomi, and offers to pay them $1 every time they roll a number 9 or lower - and if they roll a 1, he passes the die to Naomi and she pays Peter $10.  On average this almost balances out - Peter takes a slight cut, and also has to loan the money some of the time.  And it's more fun and practical for Max and Megan because they get "hits" more often, and they get paid more often, even if the payment is in smaller amounts.

In this scheme, Naomi is the bitcoin/litecoin Network, Peter is a Pool server, and Max and Megan are Miners.  Rolling dice is hashing blocks, the 1-rolls are solved blocks, and the 1-to-9-rolls are shares.  Sometimes the shares also count as completed blocks, but rarely.  Peter gets to choose the hit rate for his miners.  Maybe Paul is another pool server, with a different hit rate, payment scheme, fee, or membership.  The miners can choose which pool to use based on those criteria.

So to understand why hash rate may be high but share rate low, suppose Max buys some extra dice, and rolls three at a time - then he can win more often, as his hash rate is higher.  But if he tries to roll five dice at once, or if he rolls the dice too quickly, then some of them fall off the table and onto the floor.  In this case they don't count, so although he's rolling the dice really fast, he can't submit his shares to Peter - or, he submits them and then Peter says that they don't count.  This is analogous to tweaking your mining settings to values that appear to give a good hash rate, but in fact lead to a poor share rate.

It's also possible that it's best for him to roll 20 dice at once, and have 15 of them fall on the floor, rather than roll just three dice and be sure they're all valid - because at the end of the day, even though he wasted a lot of dice, he still got a higher share rate overall.  It comes at the expense of the hassle of rolling more dice, of owning more dice, and the wear and tear on the dice.

I know that's a bit of a tangent but I think this metaphor is very useful for intuitively understanding the mining and pooling processes.

Can someone explain to me what a share is in Litecoin mining? Or if you could point me at a list of definitions that would be very handy.

Because on my rigs if I put the thread concurrency down the hashrate goes down and share rate goes up?

Many thanks.

You should get higher hash rates when overclocking.

I would try 1000/1250 or if that is way to high, give 944/1180 a shot. Use this formula. Math Formula> .8/memory .

I get the most out of my cards using .8

Lolz, talk about flushing in the face, I feel stupid atm. Complete brain fart. My bad.

Ok, I have 2x5870

Unless you have two cards, remove one I noticed you have it placed in there twice.

As for the overclocking and same hashrate, probably have to wait for someone with a 7970 to explain the reasoning. I think people were having problems with 7k series cards not doing what they should be doing or something, I think this is why people buy the 7950's for litecoin mining.

Thanks a lot!
Now i'm getting around 600kh/s with:

But if I overclock to 900/1250, I will get always 600kh/s 

@crazyrider.

Try adding the following


Or try 5760 for thread concurrency. Not sure what 5870 uses. But my 5850's are on steroids with 5760.

Edit:
From the litecoin hardware comparison.
https://github.com/litecoin-project/litecoin/wiki/Mining-hardware-comparison#wiki-ATI_AMD_GPUs

Hi guys, i have still had problem with cgminer...

my config:
2x5870
Xubuntu 12.10
SDK 12.8
Driver 13.1

my command line:

the hashrate is very low!!!

Thanks!

I believe the first one is real time, the second one is average.

Here's mine.

stupid easy question

I`m testing my first 5970 @ these settings

--thread-concurency 8000 --shaders 1600 --worksize 256 --intensity 16 -g 1

the thing i don't get is this:



When hashing i have 2 values: 356/325Kh/s
What is the first value and what is the second, and why do they differ? (are those the cores?)

Good to know. I got two more Sapphire 7950 100352-4L's which ARE voltage unlocked, and they also appear to thrive at 925/1250/0.975, 545kH/s, 188W, 2.90 kH/J.

Try --thread-concurrency 3072 -g 9 -I 13 --gpu-powertune 20, and possibly --worksize 256
Edit: terrible advice - although it reports a higher hash rate, it just generates garbage (never gets a share).

Do try using the --powertune option though, and possibly --thread-concurrency 8192 -g 5 or thereabouts - which does seem to give me a slight edge over large concurrencies and -g 1.

Yikes, I’d definitely send them back. My rig with four Sapphire 7950s pulls 940W and that’s using an i5 730 at default clock/voltage and two different PSUs.

I don't see a problem with it software wise, but u'll most likely need stronger PSU or add 2nd PSU to the system. Does your PSU have enough PCIe 6+2 cables?
Dummy plugs aren't required anymore (as of Catalyst 12.8 if I recall correctly)

Use MSI Afterburner to control voltage etc.