20 votes
Accepted

Why doesn't the same miner always win?

Mining is not won by the miner with the "strongest ability to solve the block". Mining is a random progress-free process. Each block candidate independently has a tiny chance to be a valid ...
  • 66.1k
20 votes
Accepted

What is "buying hash rate" and how could it be profitable?

"Buying hash rate" is a synonym for a concept called cloud mining. In proof of work-based consensus systems, mining refers to a process of expending computational power to secure the network....
  • 66.1k
12 votes

Where to find exact number of hashes required to mine most recent block?

You cannot know how many hashes were actually performed for every block, because non-winning hashes aren't published. There is however a simple formula to compute the expected number of hashes a block ...
9 votes

I've tried everything from mining bitcoin to litecoin to other altcoins....why do I have no luck?

Laptop mining worked well in 2009. It is no longer 2009. Your integrated Intel GPU has the speed of a CPU, not a fast gaming GPU. Even in 2011 when CPU mining was dying and people mined on GPUs your ...
  • 8,349
9 votes

What will happen to Bitcoin when it takes years to complete a calculation?

Mining is a self-adjusting system. The difficulty only rises in accordance to the available mining power. Hence, it can neither go to a difficulty where it will take months for a block to be found, ...
  • 66.1k
8 votes

What does the mining difficulty number really mean?

Miners task is to find a hash below a target T. Obviously if T is smaller, its more difficult to find the hash number. Difficulty D is defined by: D = Tmax/T where Tmax is: 2^224 The probability of ...
8 votes

How does merged mining work?

Satoshi himself seems to be the inventor of merged mining. In his words (bitcointalk.org): I think it would be possible for BitDNS to be a completely separate network and separate block chain, yet ...
  • 736
7 votes
Accepted

What mining performance can we roughly expect from the Intel SHA extensions of the upcoming Skylake processor architecture?

Let's try to make a rough estimate. Intel's article Intel SHA Extensions gives some details on these instructions as well as sample code. The main feature is the sha256rnds2 instruction, which ...
7 votes
Accepted

What is the algorithm to create a Bitcoin mining calculator?

I want to give an extended answer as I found the pre-existing here or elsewhere in need of a bit more clarification, specifically for newcomers. Formula In order to calculate the approximated total ...
  • 251
7 votes
Accepted

What precisely does the commonly reported network hash rate refer to?

The number reported is an estimation of the number of block headers iterated through by all miners on the network. This means it refers to double-SHA256 hashes performed, not broken down to ...
6 votes
Accepted

How many GH in 1 TH?

Correct, one terahash (= 10^12 hashes) equals 1000 gigahashes (=1000*10^9 hashes). Prefixes such as tera, kilo, or milli are SI prefixes (or metric prefixes). Or you can look at it in Wolfram Alpha.
  • 76
6 votes

How to tell how many hashes/sec the bitcoin core app on osx is running?

Yes Erik, the mining feature is still built-in and you can check how many hashes your CPU can perform. Although it's pointless and you cannot earn anything, it is still a fun experiment that people ...
  • 5,328
6 votes

What is "buying hash rate" and how could it be profitable?

Although the particulars involve bitcoin, the central issue in this question is more of a Money SE question. You're being asked to invest in [industry], you just have to put up the capital, and [...
5 votes
Accepted

Who recomputes and announces the difficulty in Bitcoin?

All nodes and all clients have this logic hardcoded into them. So in that sense, everybody is responsible for understanding that every 2016 blocks the difficulty changes. The calculation that is ...
  • 5,134
5 votes
Accepted

Why is the hashrate getting so high?

Miners are competing to find valid blocks because each block allows the successful miner to collect a mining reward. The mining reward consists of an amount of newly generated coins as defined by the ...
  • 66.1k
5 votes
Accepted

What are the possible Doomsday scenarios for the 2016 Halving from 25 to 12.5 BTC per block solved?

I think you might be referring to the hypothesis that a large portion of the mining power would switch off right at the halving. This is theorized to kick off a chain reaction: Lower network hash ...
  • 66.1k
5 votes
Accepted

How miners with less power win?

That said, when the next block is being mined, again the same person will win because of his computing power. No. Higher mining power means just higher chances to mine a block. If there are 3 miners:...
  • 2,067
5 votes
Accepted

How do we know which miner or pool mined a block?

We know which miner/pool mined a block only if that miner/pool chose to identify themselves. Most commonly, they do this by inserting their name or other recognizable signature in the block's ...
5 votes

Why has BCH not received a 51% attack yet?

Because of the cost, specifically the opportunity cost. If a miner has 10% of the BTC hashrate, then if they pointed all of that mining power to BCH, they would still be losing money. With 50% of the ...
  • 63.9k
5 votes
Accepted

Are there still miners or mining pool which refuse to implement SegWit?

No, in the past year, there were only 15 non-empty-non-segwit blocks mined which account for less than 0.03% of all blocks. Non-empty blocks without segwit transactions I've looked up the last ...
  • 66.1k
4 votes

Why can't they use super computers to mine all the bitcoins?

There are two reasons why they can't flash mine all bitcoins: Difficulty and specialized hardware. First, the pace of Bitcoin creation is limited. The protocol defines how difficult it is to find ...
  • 66.1k
4 votes

What's the minimum setup to mine a block alone?

In hopes of making this a useful answer in the long run, I will show how one can answer this question in general, then give an example using today's values. Let d be the current Bitcoin difficulty, ...
4 votes
Accepted

How do I make a profit buying cloud-hashing contracts?

The short answer is cloud-hashing is not profitable as you might expect. You can still generate profit but its value is minuscule compared to the investment. To concretely answer this question, I'm ...
  • 251
4 votes

How do I make a profit buying cloud-hashing contracts?

I use this analogy for cloud mining: If you had a money printing machine would you rent it out or use it yourself? Cloud mining -no matter how you consider it- makes no sense financially. If the ...
4 votes
Accepted

When did the ASIC mining era begin?

Jeff Garzik received an Avalon miner on january 30th, 2013 and posted pictures at http://garzikrants.blogspot.com/2013/01/once-upon-time-in-china-package-shipped.html and http://garzikrants.blogspot....
  • 8,349
4 votes
Accepted

The probability that the entire network generates at least two blocks within 10 minutes?

Since current hashrate and current difficulty level should be matched up usually, we can disregard them. (Although, we could easily accommodate them if they are diverging as well.) Finding blocks is ...
  • 66.1k
4 votes

Why the nonce is difficult to find in Bitcoin?

Miners try many block candidates per second. Every candidate is different in some way, but the nonce is only one of the ways in which they differ. Other ways include the timestamp, and - most ...
3 votes

How do I make a profit buying cloud-hashing contracts?

The profit is the lesson: you got scammed.
  • 6,216
3 votes

Why doesn't the same miner always win?

Every miner is working a on different block. While they share some of the same data, there are several parts of a block which are completely up to the miner to decide, and those differences make the ...
  • 63.9k
3 votes

Why was there an non-steady mining rate in 2009?

When a large amount of hashing power enters or leaves the network, the difficulty adjustments (capped at 4x in either direction) often aren't enough to keep the average block difficulty at 10 minutes. ...
  • 7,679

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