I'll put the updates on the litecoin forum (https://forum.litecoin.net/index.php/topic,6020.0.html) since the topic is getting buried here pretty quickly.

hmm... not really... it's a bit complicated.  The most gains in the hash are eliminating loops.

For example, the kernel has an #pragma unroll which removes loop and generates the call line by line.  If a variable is unknown, #pragma unroll is not done.  Also if cgminer is not compiled with -O3 option (most are being compiled -O2, I can assure you this), the kernel will not even be unrolled at all, so it's better for you to do the unrolling manually.

EDIT: oh, and my settings are these:

"intensity" : "19",
"vectors" : "1",
"worksize" : "256",
"kernel" : "scrypt",
"lookup-gap" : "2",
"thread-concurrency" : "24000",
"gpu-engine" : "1140,1140,1020",
"gpu-memclock" : "1250"

The last card was a lemon, doesn't want to get higher than 1020, that's what's you see on the stats above (about 633~ish) still pretty decent for hash/watt ratio.

ah-- no interest?   It requires no hardware modification.  I was trying to compile cgminer to my Galaxy S4, managed to do it, but the kernel doesn't want to be accepted, so I modified the scrypt kernel code.  The good is what you see above, higher hashrate-- you might even need to tune down (like I did, to reach a good hash/power ratio), the bad is the modification is specific for each configuration, so the kernel code I have is specific to mine.  Bear in mind that cgminer can do a lot of things and can be configured to suite any GPU settings, but making it (the scrypt kernel) concentrate on a specific configuration will yield higher hashrates.  So here's what I did:

• edit scrypt130511.cl
• remove, as much as possible, looping structure
• use hardcoded constants as much as possible
• minimize arithmetic operations (addition, subtraction, multiplication, and division) by calculating the exact values from hardcoded settings (thread concurrency, worksize, gap)
• minimize calling custom functions and incorporate them to the function caller itself.
• save!
• remove all scrypt130511......bin files, because this is the compiled kernel that cgminer uses for the current setting
• start cgminer

The readability and maintainability of the code is of course affected, but we don't need this-- we want the kernel to be as efficient as possible!

A month ago I was hashing like this:



You can see that the highest core-engine/memory there is 1145/1250.

Fast forward now, with lower core-engine/memory settings:


Don't mind the Kh/s.  I tweaked my BAMT to display it in Kh/s.  See the numbers above?  That's 700+ on the same MSI 7950 being reached with lower engine clocks, all other settings the same!  Got you interested now?

Just when you've achieved the maximum stable configuration of your rigs that are running for months now, this is a guide to achieve higher hashing performance out of your GPU.

(Stay tuned-- I'm just excited to share this now with all the nights I've spent doing this, so I'll let you hang there for a while now... in the meantime, please post your current scrypt settings below)

well with all the other replies I thought it was missed, having this kind of answer is better since now I know I need to proceed with a different approach in solving it.

erm.. bump?

I managed to compile cgminer in Android and trying to run it in my SGS4 with opencl, and I have some problems running it (spare me the "why bother" response, I think running cgminer in my phone is kinda cool, and with the advancement of GPUs in the mobile space, you'll never know  )

Anyway-- running cgminer -n gives me:


So it should be ok, right?  But trying to run cgminer with the usual parameters (--scrypt -o <host:port> -u <username> -p <password>) gives me:

I compiled cgminer with OpenCL Adreno SDK instead of AMD SDK (for obvious reasons).

"Method of swinging on a swing"
US Patent no. 6368227 B1  

pm'ed 

Still looking    To be specific, somewhere I can drive in the range of Rotterdam/Zoetermeer/Leiden 

I broke one when I was moving my setup to a new box  , so I need a new one quickly.
Let me know if someone has an extra that I can pick up immediately.  I live in Den Haag.

I can understand as long as I know the context, the problem is still speaking

From there, it seems now the difference for my current provider is only .00xx, so not really worth the hassle in switching.

Dank u wel!

Excuse me, but I will ask in English (but you can reply in Dutch )

Which electricity provider has the best tariff for mining?  I'm currently with Nuon which is about 0.2281 p/kwh.

shame, should have been perfect for me-- but I plan to run at least 3x 7950s and the motherboard doesn't support more than 2..!

No no no-- because you can't run "ipkg update" without ipkg-- and from the message you sent:


That means you got "ipkg" already.  There's nothing there in "/opt/lib/ipkg/lists/cross",   but there is something in "/opt/lib/ipkg/lists" which is the cross file (that contains packages that you can download).

EDIT: ah-- I see what you mean on the error.  Ignore this:


and do this:

it will show you something like this (example for sysfsutils):


take note of the url and do

do the same thing for wget-ssl:

then do
where filename1 and filename2 is the name of the .ipk file of libidn and wget-ssl.  I'll put this in the guide above.

First: which DSM version do you have?

I see you got until ipkg update, that means you can get the precompiled binaries for the toolchain.
When you try these commands nothing happens?


type in

and paste here the output.

Since BitFurys are priced in euros, will you accept payment in euros (SEPA/paypal)?

The NAS I have (410j) consumes about 42w, but since it's always on, it's "free" electricity so to speak.
The native compiling of cgminer/bfgminer should have been straightforward, but there are just some nags that you would encounter and I merely pointed the solution to it

So theoretically when chips are received in October the custom boards are ready for assembly (1 week?) and delivery (another week?)

Hi Marto,

What's the 'theoretical' timeline on designing the custom board + production when you get the specs from Punin?
What's the expected cost of the custom board (with 16 chips)?