A sharp drop in computational power
in short, it is a redistribution of computing power driven by interests.
Bitcoin mining is a process that uses computer hardware to calculate the location of bitcoin and obtain it
mining is an incentive process to record data in the bitcoin system. In the bitcoin system, indivial users have the right to pack blocks after calculating a specific hash value by using CPU or GPU to hash
and in order to reward this user for packing blocks, the system will give a certain amount of bitcoin as reward. Because this process is very similar to "mining" in real life, most people call this process mining. In addition to bitcoin, other electronic virtual currencies can also be obtained through mining rewards, such as Ethereum, Monroe and so on
extended data:
mining risk:
1, currency security
the withdrawal of bitcoin requires hundreds of keys, and most people will record this long string of numbers on the computer, but frequent problems such as hard disk damage will make the key permanently lost, which also leads to the loss of bitcoin
2, system risk
system risk is very common in bitcoin, and the most common one is bifurcation. Bifurcation will lead to a drop in currency price and a sharp drop in mining income. However, many cases show that the forking will benefit the miners, and the forked competitive currency also needs the miners' computing power to complete the minting and trading process. In order to win more miners, the competitive currency will provide more block rewards and handling charges to attract miners. Risk makes miners
Some new virtual digital coins can be mined by computer, such as eth, Zec, Monroe, XRB, etc
because the whole network computing power required by this kind of token is not high, the probability of hash collision of the computing power of personal computer can find out the answer in a short time, so as to obtain the block reward. However, this kind of token generally has little value, or has no high risk, so it doesn't mean much
extended data:
mining risk:
1. Electricity charge:
to make the graphics card full load for a long time, the power consumption will be quite high, and the electricity charge will be higher and higher. Many professional mines at home and abroad are operated in areas with extremely low electricity charges, such as hydropower stations, while more users can only mine at home or in ordinary mines, so the electricity charges are not cheap. Even in a certain residential area in Yunnan, there was a case of crazy mining, which led to a large area trip of the residential area, and the transformer was burned
2. Hardware expenditure:
mining is actually a competition of performance and equipment. Some mining machines are composed of more such graphics card arrays. With dozens or even hundreds of graphics cards, the cost of hardware and other costs is very high, and mining has a considerable expenditure
in addition to the display card burning machines, some ASIC (application specific integrated circuit) professional mining machines are also put into the battlefield. ASIC is specially designed for hash operation, and the computing power is quite strong. Moreover, because their power consumption is far lower than that of the display card, they are easier to form scale, and the power cost is also lower. It is difficult for single chip display to compete with these mining machines, This kind of machine costs more
3. Currency security:
the withdrawal of bitcoin requires hundreds of keys, and most people will record this long string of numbers on the computer, but the frequent problems such as hard disk damage will make the key permanently lost, which also leads to the loss of bitcoin
4. System risk:
system risk is very common in bitcoin, and the most common one is bifurcation. Bifurcation will lead to a drop in currency price and a sharp drop in mining income
however, many cases show that the forking will benefit the miners, and the forked competitive currency also needs the miners' computing power to complete the minting and trading process. In order to win more miners, the competitive currency will provide more block rewards and handling charges to attract miners. Risk makes miners
the power consumption of bitcoin mining machines is different according to different machines take Shenma 68T, the fastest mining machine in wet season, as an example. Suppose that the electricity charge is 0.22 per kilowatt hour in half a year in wet season and 0.34 per kilowatt hour in dry season, the wall power consumption of Shenma 68T's second-hand machine is 3264w, and the actual power consumption is 3500W, then the daily power consumption of a Shenma M20S 68T machine is 3.524 = 84 degrees, Annual power consumption 84 * 365 = 30660 degrees
according to the latest mining difficulty, a Shenma 68T machine can dig 0.00064836 BTC a day, and 10 machines can dig 2.366514 coins a year. The mining difficulty of the premise remains unchanged, but according to the current situation, it is assumed that the mining difficulty will increase by 30% from now to next June, and by 2.5% every month. It is estimated that 85% of the original coins should be g, that is, 2.012 coins. Ten machines of Shenma 68T can dig almost 2 coins a year
to sum up, the power consumption of ten Shenma 68T machines in a year is 306600 kwh, which can dig almost two coins
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extended data
the risk of mining machine
1. Hardware expenditure
< P > mining is actually a competition of performance and equipment. Some mining machines are composed of more such graphics card arrays. With tens or even hundreds of graphics cards, the hardware price and other costs are very high, There is considerable expenditure in miningin addition to the display card burning machines, some ASIC (application specific integrated circuit) professional mining machines are also put into the battlefield. ASIC is specially designed for hash operation, and the computing power is quite strong. Moreover, because their power consumption is far lower than that of the display card, they are easier to form scale, and the power cost is also lower. It is difficult for single chip display to compete with these mining machines, This kind of machine costs more
2. Currency security
the withdrawal of bitcoin requires hundreds of keys, and most people will record this long string of numbers on the computer, but the frequent problems such as hard disk damage will make the key permanently lost, which also leads to the loss of bitcoin
3. System risk
system risk is very common in bitcoin, and the most common one is bifurcation. Bifurcation will lead to a drop in currency price and a sharp drop in mining income. However, many cases show that the forking will benefit the miners, and the forked competitive currency also needs the miners' computing power to complete the minting and trading process. In order to win more miners, the competitive currency will provide more block rewards and handling charges to attract miners. Risk makes miners
The first half: on November 28, 2012, the 210000 block was excavated, and the block reward was halved for the first time, and the block reward was 25btc
the second half: on July 10, 2016, starting from the 420.000 block, the bitcoin reward of each block was halved to 12.5btc
the third half: on May 12, 2020, bitcoin reward will be halved to 6.25btc
the next half: on May 9, 2024, bitcoin reward will be halved to 3.125btc
but bitcoin mining as an infrastructure, if bitcoin can continue to exist, although the income of mining is reced, for the security of the whole bitcoin network system, some big bitcoin companies may invest in mining to maintain the security of bitcoin network system. In addition, the future of bitcoin will become more clear and bright. Bitcoin's computing power will not decrease, but will increase.
the risk of platform subscription currency is great, so we suggest you stay away from it. Bitcoin home has also reported similar incidents of running away from the subscription currency platform before. Subscription currency platform is small, information is not open and transparent, and it is not necessarily an open source cryptocurrency. Some platforms may gather a lot of funds on the platform and run away. They may also encounter the selling of Dazhuang, which leads to the collapse of Shanzhai coin. The development and operation team will also choose to develop a new Shanzhai coin.
Check whether the graphics card is mine card or not, you can refer to the following three points:
1, st
when the graphics card is running, it needs heat dissipation, the heat dissipation is mainly the fan on the graphics card, so the st on the fan will give us some judgment. Generally speaking, the self used video card and fan will not always run at full speed. The cotton gauze of all kinds of textiles in the room is scattered, so the st on the fan is often mixed with cotton wadding
extended data:
the maintenance of the graphics card is as follows:
1. The chassis is well ventilated, which can protect the graphics card and all the hardware in the machine, and prevent the high temperature from causing the running speed to drop, crash or even burn. The machine room is hot. In summer, you can take down the side panel of the chassis to help heat dissipation, or add a fan to help heat dissipation. If conditions permit, it is recommended to use water cooling to improve the working efficiency of the graphics card
2. The interface of the graphics card and the display are connected correctly on the street, and the virtual connection is easy to be interrupted frequently or ignited, which will cause the interface of the graphics card to burn down.
3. The effect of overclocking on the graphics card is not very obvious. On the contrary, it is easy to cause a huge increase in heat and slow down or even burn down of GPU
4. Dust cleaning, no matter the Chaka or motherboard or other components, will inevitably proce st after a long time. It is necessary to remove the chassis and carry out st removal work to ensure the normal work of each component
reference: network bitcoin miner
because the network wide computing power required by this kind of token is not high, the probability of hash collision of the computing power of personal computer can find out the answer in a short time, so as to obtain block rewards. However, this kind of token generally has little value or high risk, so it is not of great significance< br />
extended data:
mining risk:
1. Electricity charge problem:
if the graphics card "mining" needs to be fully loaded for a long time, the power consumption will be quite high, and the electricity charge will be higher and higher. Many professional mines at home and abroad are operated in areas with extremely low electricity charges, such as hydropower stations, while more users can only mine at home or in ordinary mines, so the electricity charges are not cheap. Even in a certain residential area in Yunnan, there was a case of crazy mining, which led to a large area trip of the residential area, and the transformer was burned
2. Hardware expenditure:
mining is actually a competition of performance and equipment. Some mining machines are composed of more such graphics card arrays. With dozens or even hundreds of graphics cards, the cost of hardware and other costs is very high, and there is a considerable expenditure in mining
in addition to the display card burning machines, some ASIC (application specific integrated circuit) professional mining machines are also on the battlefield. ASIC is specially designed for hash operation, and the computing power is also quite strong. Moreover, because their power consumption is far lower than that of the display card, they are easier to form scale, and the electricity cost is also lower. It is very difficult to compete with these mining machines, This kind of machine costs more
3. Currency security:
the withdrawal of bitcoin requires hundreds of keys, and most people will record this long string of numbers on the computer, but the frequent problems such as hard disk damage will make the key permanently lost, which also leads to the loss of bitcoin
4. System risk:
system risk is very common in bitcoin, and the most common one is bifurcation. Bifurcation will lead to a drop in currency price and a sharp drop in mining income
however, many cases show that the forking will benefit the miners, and the forked competitive currency also needs the miners' computing power to complete the minting and trading process. In order to win more miners, the competitive currency will provide more block rewards and handling charges to attract miners. Risk makes miners.
an important feature of modern audit is to make full use of modern economic statistics technology and methods, and to replace comprehensive audit with sampling review, so as to improve audit efficiency, ensure audit quality and rece audit risk
in the early stage of the development of internal audit, most of the auditors basically used the method of comprehensive and detailed inspection in the audit practice to check all economic business and accounting documents. With the continuous development of enterprise proction, the continuous expansion of business scale and the rapid growth of economic business volume, there will be some difficulties in the specific audit, whether from the audit cost or from the audit time. With the development of internal audit, auditors graally use audit sampling technology in their work, standardize audit sampling work and improve the quality of audit sampling work. Many countries have formulated audit sampling standards one after another. In 1981, the United States issued audit standards Announcement No. 39; In 1996, China formulated and issued specific standards for independent audit No. 4 - audit sampling
according to the statement of specific standards for independent audit No. 4 - audit sampling, sampling audit is that auditors select a certain number of samples from the overall audit object to test when implementing audit proceres, and infer the overall characteristics according to the test results
first, the necessity of using sampling audit
the needs of social and economic development. In the initial stage of internal audit, the social and economic activities were not complex, the scale of enterprises was small, and the accounting data for recording economic business was not too much. However, with the development of market economy and the improvement of social proctivity, the scale of enterprises was expanding, and their economic business was increasing and diversified, especially the emergence of group companies and multinational companies, With the increase and complexity of economic business and accounting records, it takes a lot of time, manpower and material resources for auditors to conct a comprehensive and detailed investigation of all economic business and accounting records, which is not only too expensive but also very difficult. Audit technology and methods should adapt to the development of social proctivity, audit sampling technology can be proced and developed
in line with the principle of cost and benefit. According to the principle of audit importance, auditors do not need to make a comprehensive judgment on all economic business. As long as they can properly use the audit sampling technology and review the local samples, they can infer the overall characteristics. Under the limited audit resources, they can collect sufficient and appropriate audit evidence to form and support the audit conclusion
the reliability of audit conclusions is high. Statistical sampling is to scientifically determine the sampling scale according to the principle of mathematical probability theory of economic statistics. Its sampling risk is predictable and controllable. The samples are selected by random method with less subjective factors. The sample results objectively reflect the overall characteristics. The effectiveness of the sampling results is not affected by the auditors' experience and professional judgment ability, so the results are more scientific It is more reliable, but it can not be considered that statistical sampling does not need professional judgment of auditors. For the determination of audit sampling objects and estimation error rate, auditors need to use personal experience and professional judgment< Second, the characteristics of sampling audit:
sampling audit is different from specific audit. Specific audit refers to 100% audit of all items in the overall object, and form audit opinions according to the audit results. The sampling audit is to select part of the sample from the overall audit object according to the statistical principle, infer the overall and express audit opinions according to the sample
audit sampling cannot be equated with spot check. Spot check, as a technology, can be used for pretrial investigation, audit emphasis and audit evidence. There is no strict requirement in use. As a kind of audit method, audit sampling needs to use statistical principles and implement in strict accordance with the specified proceres and sampling methods
sampling audit can be generally used for adverse audit, follow-up audit, letter audit and other audit proceres, and can also be used for compliance test and substantive test; However, it is not suitable for auditors to use audit sampling in inquiry, observation and analytical review. 3、 The application of statistical sampling technology needs to be considered
according to the overall characteristics of audit, it can be divided into attribute sampling and variable sampling. Attribute sampling is often used in the compliance test of enterprise internal control system. Its purpose is to determine the effectiveness of the internal control system of the enterprise. It is generally divided into fixed sample sampling, stop and go sampling and discovery sampling. Variable sampling is often used in the substantive test of account balance of enterprise accounting statement. Its purpose is to determine the error of asset or liability items. Generally, it is divided into unit average calculation method, difference estimation method, ratio estimation method and monetary unit sampling method
focus on audit risk. Audit risk is that the audit conclusions obtained by audit sampling can not fully reflect the uncertainty of the overall situation. Risk is divided into inherent risk, control risk and inspection risk, and audit sampling is related to control risk and inspection risk. Control risk refers to the risk that internal control can not prevent or discover important errors in accounting statements; Inspection risk refers to the risk that auditors can not correctly evaluate the amount of the statement. The application of sampling technology in compliance testing can provide auditors with information directly related to the evaluation and control of risk; The application of sampling technology in substantive testing can help auditors to quantify inspection risk
rece sampling risk. Sampling risk is the possibility that the audit conclusions derived from sampling may not be consistent with the overall characteristics of the auditee. It is different from the nature of non sampling risk caused by improper audit proceres and methods or misunderstanding of audit evidence. Sampling risk can be divided into two categories: one is the risk of lack of trust, which means that the proportion of problems or errors in sample items is greater than the proportion of actual problems or errors in the audited population. It will lead to auditors to perform additional audit proceres and rece audit efficiency. The second is the risk of over reliance, which means that the proportion of problems or errors in the sample items is less than the proportion of the actual problems or errors in the audited population, which will lead to the formation of incorrect audit conclusions. Excessive trust risk is the most dangerous risk for internal auditors, which will make the audit unable to achieve the desired results
understand the scope of application of sampling methods
audit sampling preparation is a modern audit method, which is not suitable for all project audits. When the projects in the overall audit object are very important, the audited project has greater audit risk, or it is not favorable from the perspective of cost-effectiveness, the audit sampling method should not be used generally. When determining the audit object, auditors should fully consider its relevance and integrity; Relevance means that the overall audit object must conform to the specific audit objectives; Integrity means that all the items involved in the realization of audit objectives must be included in the selection of audit population. Detailed investigation method should be adopted for the projects with higher audit risk, sampling audit should be adopted for the projects with more audit content and relatively small audit risk, and combined with analytical review method, so as to minimize the audit risk. The key lies in the design of sampling samples according to the characteristics of various sampling methods, mainly in the design of audit error, evaluation of sampling risk and determination of overall error according to audit experience
the application of statistical sampling technology must be based on the premise that the enterprise has a sound internal control system. If the enterprise has a sound internal control system, the possibility of errors and malpractices in economic activities will be reced, and even errors and malpractices can be found quickly; At present, with the development of computer technology, there are special sampling software, which can be used for random sampling by computer; Although statistical sampling has many advantages and solves the problem that non statistical sampling is difficult to solve, it is still necessary to use decision sampling in some cases.