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15

The scrypt() algorithm has at its core a routine called ROMmix. Basically, it defines V(1) = hash(message) V(2) = hash(hash(message)) V(3) = hash(hash(hash(message))) ... and it calculates V(V(V(V(...(message)))) Since computing V(n+1) requires computing V(n) first, the most efficient way to do this is to cache all of the previously-computed ...


11

Any CPU can still be used to mine Litecoin, although much less effectively as a modern AMD GPU could. Mining with a CPU gives you very bad hashrate therefore I wouldn't recommend it. Even a high end CPU will not give you the hashrate of a mid range GPU. You should use a graphics card (GPU) to mine litecoins or switch to another coin Additional Information:...


11

Alright, I finally managed to fix my bugs and get a full roundtrip. Here is an example for a full communication with a Pool. I don't explain everything in detail as the API description can be found elsewhere. a) Suscription {"id": 1, "method": "mining.subscribe", "params": []} {"error": null, "id": 1, "result": [["mining.notify", "...


8

I think that Tim S. may have the answer with his comment about endian-ness. Your observations about the nonce having its lowest byte zero (being a multiple of 256), are with respect to the little-endian byte order of the block itself. From the perspective of a big-endian machine, these are statements about the high byte of the nonce. So consider a miner ...


7

Litecoin uses a different proof of work than Bitcoin, so that hardware won't be compatible(it won't be solving the right problems). One of the motivations of Litecoin was to make CPU mining viable by making it difficult to create efficient GPU/FPGA/ASIC miners, so it's unlikely that you can find specialized hardware for this purpose. I think that some GPUs ...


6

The scrypt-jane modification allows the N in scrypt(N,1,1) to change. Litecoin uses scrypt(1024,1,1). GPU miners haven't taken this into account. But now you have the opposite issue. Instead of the GPU miners getting everything, it's the datacenters who have the advantage.


6

Seed nodes are important even for SCRYPT coins. You need to edit the source code in particular the DNS seeds and IP address seeds in the net.cpp file. You can run this on a VPS or any always on internet connection with a static IP address. Litcoin Net.cpp The DNS seed node resolves to multiple IP addresses that are all running their own *coind instance ...


6

There are a few other GPUs that do a bit better according to this list: https://litecoin.info/Mining_hardware_comparison I think this is just based on user feedback to the Wiki. The ones with a lot more khash/s are multi-card setups. Really if you have free power you should mine with whatever you can afford, then add more cards after you have coins and ...


6

It's the same: the proof-of-work is that the scrypt hash of the block header must start with a certain number of zeros (or, more precisely, be numerically less than a certain target value). However, the scrypt hash is not what's used as the block ID; rather, the sha256d hash (double sha256) is used instead. The sha256d hash doesn't have to follow any ...


5

The most common pronunciation I have heard is /skript/


5

Found a helpful post at litecointalk: It won't work because the aux work must be explicitly provided by the merge coin. All of these coins cloned from Litecoin lack that code as Litecoin doesn't have it. As a result you cannot merge mine these coins. It is the same reason you can't merge mine Terracoin or Freicoin with Bitcoin. Freicoin considered ...


4

This might interest you https://bitcointalk.org/index.php?topic=45849.0 FPGA implementation was investigated, too, and it appears somewhat lacking in performance compared to a CPU about 1/7th the price, thus being quite non cost-effective


4

No, you can't mine Litecoin with any of Butterfly Labs' products. There is an ASIC miner in development by Alpha Tech http://alpha-t.net/ that they claim will be able to.


4

I do not think there is a formal convention. Your best bet is probably to inquire at the inventor, the one-man company tarsnap. Start at their webpage about scrypt. Since the important point is cryptographic security and because of their unix-like naming (tarsnap!), I'd say this probably follows the same convention that makes ssh the secure shell. Hence my ...


4

Currently, for a custom-built high-performance desktop, 16 GB of RAM (or even 32 GB) is typical, while one of the best GPUs, the AMD Radeon HD 7990, has 6 GB of GDDR5. Suppose the memory requirements were raised to 4 GB. That means that each thread will require 4 GB, so a CPU can mine on 4 threads at a time (16 / 4 = 4), while a GPU can only mine on 1 ...


4

No. Bitcoin does not use Scrypt, so you cannot use something that mines Scrypt to mine Bitcoin. Furthermore, the Antminer S3 is a Bitcoin miner, it can only mine SHA256d coins, such as Bitcoin. So it cannot even use the Scrypt algorithm or mine any coins that use Scrypt.


3

I think the important factors for scrypt in OpenCL are as follows GPU core clock rate Memory clock rate / memory bandwidth Memory bus width / channel Computation Units Processing Elements You can check out in Programming Guide of AMD Accelerated Parallel Processing. single or double precision of floating number does not matter. Either SHA-256 or scrypt is ...


3

How do I work out the SHA-256 and scrypt hashrate You can look up your hardware e.g. here (BTC) and here (LTC). But I think it's much easier and more accurate to just try mining different coins for couple hours and measure hashrate directly. For the Power(W) box, do I enter in my computers PSU wattage? I think it's 650w PSU wattage is max. power it can ...


3

Tenebrix uses Scrypt as the proof of work algorithm. Scrypt was said to be GPU resistant due to the in memory look up tables the algorithm uses. Most people no longer mine tenebrix with CPUs and use GPUs instead. Mining tenebrix with a GPU you can expect to hash at approximately 1/1000th the rate you would get on the same card mining bitcoins. For example, ...


3

In my experience scrypt mining on GPUs is quite susceptible to cause HW errors and wrong nonces if the parameters are not chosen to match the GPUs the algorithm is run on. As the SCRYPT-README file of cgminer states: The reason this is crucial is that too high an intensity can actually be disastrous with scrypt because it CAN run out of ram. High ...


3

CPU is virtually useless for scrypt based coins like litecoin, stick to GPUs, for now. Here is a comparison of the top GPUs you can buy for mining, with user submitted settings. http://coinpolice.com/gpu/


3

The amount of memory that scrypt uses can be adjusted to get the desired behavior. If a particular CPU has enough L2 memory to hold all that's needed for a particular scrypt use case, then the performance of system memory will not be relevant. Scrypt-based coins can increase the memory requirements dynamically as one way of increasing the mining difficulty.


3

For Litecoin, if memory size is increased in processing the Scrypt algorithm, for example to 384 kB instead of 128 kB (...), would the typical CPU architecture (...) be likely to see a corresponding increase in performance? No, it works the opposite. If you increase memory, which is used by the scrypt to generate a single hash, the time it takes to ...


3

If you're scrypt mining a SHA256d coin, you will probably never get any shares accepted. You need to use the mining algorithm the coin uses.


3

No, the Jalapeño is a Bitcoin miner, it solves the SHA-256d hash function. On the other hand, Dogecoin uses the Scrypt hash function. The two are not compatible, and as far as I know there is no Scrypt ASIC being sold, yet.


3

The use of scrypt vs SHA256 has an impact on proof of work but no impact on the signature scheme or transaction structures. The only thing that should impact you when using this library is the address prefix that differs with altcoins. The standard address prefix for Bitcoin is 0. For Dogecoin for example it's 30. So you could reuse that same library and ...


3

When a mining ASIC claims to run at 1 MH/s or 10MH/s or even 1000 GH/s, at what difficulty 10 MHash/s means that the chip can do 10 million hashes per second, regardless of what the difficulty is. The difficulty changes how many blocks you find, but it doesn't change how many hashes the chip performs. and with what algorithm is that measured against? It'...


3

The Scrypt algorithm started out as an "ASIC-resistant" algorithm, but it isn't anymore. Because it is highly memory-intensive, it was thought to be prohibitive to design and use ASICs for it. Initially it kind of was. With cost of memory decreasing and the necessary research put in -- in order to unlock the profit potential attainable using Scrypt-capable ...


3

Wallets will only consider outputs to be theirs if it is something that it can spend from. This usually entails checking the output script against the set of scripts that your addresses will be used to generate. So even if you can sign for something, if the script does not match any of the scripts stored in your wallet, then it will not consider that output ...


2

No. A GPU will almost certainly always be faster than a CPU for Litecoin mining. See the Litecoin Mining Hardware Comparison chart.


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