There is no "one-size-fits-all" when it comes to choosing a mining gear, it's a combination of a few factors.

1- Your power rate and voltage
2- Your budget
3- Your power and space capcitity

These are a few major factors that need to be considered, there are a few more, but you basically want to evaluate all things to make the right decision, the only common thing would be to avoid mining gears that are known to have a high failure rate, other than that, it's case-by-case.

I think there is a misunderstanding here, the control board reads the general model of the PSU not something like a special serial number, in other words, you can use any PSU from a different miner as long as they are the same exact model, so for resellers, they have APW9+ for example, it will work on all miners that have that PSU model, the control board will real APW9+, check the voltage and some other parameters and it will work just fine.

The problem is, it's hard to source these PSUs in the first place.

No, as long as your router has DHCP enabled the miner will get an IP address and you should be able to find it in the DHCP client list, an easier way would be to download something like "angry IP scanner" which will scan your network and show the IP address of all miners connected.

Ya right, it hasn't hit a block for 358 days so far, if that isn't enough lag not sure what is.  


Not sure why are you pasting your resume here, you posted a false claim which says:


I told you BOs is still open source, and what you are talking about is the BOs+ which is a different version, yet again you came up with another false claim and said they are the same, I asked for proof, and I have yet to see one.

You say it's the same but "with changes", well, all firmware versions have many similarities since they basically almost do the same thing and deal with the same drivers/hardware, unless that is your definition of "the same" then BOs and BOs+ are different firmware versions and as often, you are wrong.

I am asking about a specific code, BO+, how did Kano come to the conclusion that it is the same as the orginal one,  I suppose someone who wrote firmware from scratch would use the proper obfuscation tools to protect their code against RE,  i honestly believe Kano has not even looked into the firmware, and he is making shit up, if not - i'd love to see code comparision between the two.

LOL, you sure are clueless,  you probably don't own any mining gears and you are still stuck in the 2016-2017 era. You need to wake up and smell the coffee, most certainly the standard S9s don't make anywhere close to 1/4,  it is so funny i don't even want to discuss it.


Your comprehensing skills are lagging worse than your pool,  I said the only S9 source code available is the S9 as is, there is no source code available for the S9k and S9se.





This is another baseless claim, how do you know how different or similar the + version is without being able to look into the code of both versions, of course you don't and you are just saying stuff you have no clue about.

What instructions state the 8 to 10 minutes crap? ignore that, when the two lights stay solid and then go off, in most cases the reset is complete, the green light won't come on after the reset because the S9 SE comes without any pool/worker details by default, so you will need to find it's IP address and type that into your browser, enter your pool url/ worker/ password and hit save, wait a few minutes that miner should be up and running assuming it doesn't have any other issues.

Those only make a very small percentage of all the gears in the world, besides, the S9 as is, is an old obsolete model and mostly dead, the newer versions have different firmware which isn't open-source, so it's safe to say that the vast majority of OEM firmware is closed source, I know you like to make it seem like that isn't the case, just to justify allowing them to use your pool, but that's for a different topic.




Wrong, BOs is fully open-source, BOs+ is not, those are two different firmware, perhaps you should do some reading before claiming things that are far from accurate.

Why would anyone attempt to prove you wrong? While the numbers you use can be way too different for others,  the matter of the fact is that in every 10 combinations at least 6 will be a loss, maybe 1 will break even, and probably only 3 will win (assuming the combinations are reasonable and real-world numbers)

Paying $8000 for an S19 is the first mistake, and using over-priced gears for your inputs will easily end up in your favor as far as your theory goes, but that does not mean "You Can't Mine Bitcoin Profitably", and I can easily prove you wrong.

on the 27th of June, I got my hands on 40 S9is with a total cost of $6,000 plus $3400 for shipping from China, that's a total of $9400 or $235 per S9i, I received the gears on the 9th of July and they were up and running on 11th of this month.

The total cost in USD was about $9400 or 0.285 BTC.


The average daily income for these gears has been about $145 / 0.0048BTC a day, I have free power where these gears are hosted, and thus I am almost guaranteed to ROI within 2 months or 3 months in the worst-case scenario, at least for theBTC investment I made.

The key point here is that getting those S9s for that price wasn't something everyone could do (ask most resellers on telegram/Alibaba and you are unlikely to find anything below $200, am also sure other people who have the right contacts got them for less than what I paid for) and the second point is the fact that I have free power, which is also something that most people don't have.

I am nothing but a small fish in a huge ocean, but when you think of mining, you are essentially competing against a dozen folks like me, those who have access to better gear prices and free or very cheap power rates, when you pay $8,000 or even worse $15,000 for an S19, you are asking for troubles and you are more likely to lose money than not.

What are the odds that he will find any information related to keeping a miner? absolutely ZERO.

I'd be very surprised if I saw a book on how to "keep a mobile phone" despite the fact that the mobile phone industry is many decades old, let alone ASIC miners that are less than a decade old and become obsolete in no time.

OP, keeping a miner is rather simple.

1- Ensure you have perfect electricity set up
2- A stable internet connection
3- Good clean airflow
4- Clean the miners once a while
5- Take basic security measures by using strong passwords and resetting all used miners you buy.

That's pretty much all you have to do to take care of your mining gear, it's common sense and almost everyone can do it, keeping a miner is relatively easy, making a profit from the miner is the challenging part.

This does make sense, but we don't know for certain, because even OEM firmware is closed source, and we know for certain that every miner has its own unique serial number which the firmware detects, so there is a possibility that the miner's ID could be leaked to the pool in one way or the other, it's very unlikely that the pool will request it, and even if it did, we still don't know if the miner will pass such info to the pool, but as long as we don't know the code for the firmware, everything is still possible.


To be honest, most of his questions are rather weird, but I find some of them interesting, I have been mining for years and have never thought of such things.

The firmware is called "multi-option user firmware" under the name "Antminer-S9-xilinx-201907302037-autofreq-user-Update2UBI-NF-sig.tar.gz", the -2TH will put him at about 1000w, not sure if that will help, he would probably need to disconnect one board.

Gear prices in China went up about 15-20% in the last couple of days, and since the price has been stable or more to the downside than up, and the difficulty hasn't changed in the past few days and thus profitability wasn't a factor this means

1- The Chinese are relocating to different regions in China.

Or / And

2- The demand from outside of China spiked.

The reason is somehow irrelevant, the outcome however is rather clear, at 32k Bitcoin we will unlikely witness any difficulty drop below the current levels, so if I had to bet, I would bet on the difficulty to go up (assuming the price doesn't collapse), and then remains the question of how much up? if it's the Chinese relocating within China then the rise will be fast, if it's overseas, it will be as small as you think.

My long-term projection remains the same, we will go up slowly, we won't see the ATH difficulty level any time soon, probably not until 2022.

It's different for every model or a set of models, for example, the APW9's output is 14.5V-21V DC which is the same voltage for the APW9+, but each is suitable for different models, you can't mix PSUs, the miner won't start.

Also, it's isn't just a matter of matching the voltage, most new miners connect to the hash boards using direct busbars at a very specific orientation, so even if you managed to trick the firmware to accept a different PSU it will be hard to deal with the connectors, so long story short, it will be extremely difficult to use any PSU except the one that the manufacturer itself makes.

This is why one should always stick to buying the same model, doing so, you end up with spare parts to revive different miners, if you have 10 gears, one loses a PSU, another loses hash boards and the 3rd one loses a control board, you can mix the parts and end up with only 1 dead miner as opposed to 3, but if you buy 1-2 of every model, you will be in trouble.

CoinEx is the largest exchange for this coin, and even there, it has a very low volume, and thus buying/selling large amounts won't be the easiest thing in the world.

On a side but related note: the last a few comments (including mine) are somehow off-topic as far as mining bitcoin is concerned.

There are other components that fail, but most of the time is a dead chip or a few of them, if you think that is a small problem which can be easily and cheaply fixed then you need to do more research, the average fix for a chip would be in the $100 range including labor, of course it depends on where you live, but if you are going to buy a used gear for $400 today, chances are by the time it needs fixing you can buy it for $200, fixing a single chip for $100 or even $50 does not make any sense, so more often than not and especially with the old gears, once a single chip dies, the whole board is rendered dead as far as logic is concerned.

Another common issue would be the PSU, many gears are known to have fragile PSU, and the problem is, most gears today don't use a universal 12v PSU which you can buy of anywhere, they rather use their own designed built-in PSU which in most cases are hard to find, many people have perfectly working miners that need PSU and can't find them.


I am not sure about "drastically" but at least in theory overclocking any gear will reduce its lifespan, but it's always a question of how solid that piece of gear is, I have seen overclocked gears that run over 100c all day long for months and months without an issue, on the other hand, many gears that run on stock settings died way too soon, of course, if the latter group was overclocked - chances are they would have died a lot sooner, but it all boils down to how solid that gear is.

Many routers (including the cheap ones)have VPN functionalities built-in, you just need a proper VPN service that is compatible with the protocol your router supports, I think NordVPN does not have l2tp and pptp anymore so if those protocols are the only option, you are going to need to use a different VPN, but all in all, it's not that complicated to set up.

The other option would be going through your PC, I wrote this step-by-step guide on how to do that, while it may seem like it's a lot of steps, it's rather simple even if you have no clue about networks and how they work.

There is no answer to this question, and am pretty sure you won't find any documented studies in that regard, the ASIC mining industry is relatively new, and gears become obsolete quite too often, so they switch hands very fast from the ones who have high power rate to those who pay less until it eventually ends up in the hands of those who have free power or the gear could be scrapped.

With that in mind, most used gears have little to no information on them, you buy a used gear that has changed hands a couple of times until it got to the seller, you don't know if it has been mining for a month or a year, and thus whatever numbers you get to will be far from accurate.

The second issue is the fact that the quality of every mining gear is very different, every model is different, and even within the same model every batch will be different, you are talking about Chinese manufacturers that have little to no quality control, so if you ask me about Bitmain failure rate regarding the 17 series, It has now easily passed 80% failure rate in less than 2 years, if you ask phill he got lucky the s17 pro version and has almost no failure rate, we bought the same gears, probably a few months apart and have very different failure rate.

My S9is and S9js have been pretty solid, my S9ks and S9se died in no time, my M21s has been mining day and night with no issue, some other people have their M21s die in a few months, there are no official numbers on which you can count on, even the manufacturer themselves don't reveal those numbers (assuming they have them), the only time Bitmain admitted a high failure rate was when Jihan Wu had to calm down the angry Chinese miners who were complaining about high failure rate on the 17 series, and he did admit that the rate was above 30% or more if I could remember the article correctly, but aside from that, there are no official statements.

As a general rule, you should assume that a brand new gear would last you 12 months, a used one will last half that period, while that isn't going to always be the case, it's not uncommon for gears to die in a few months, so if you place your business model on the assumption that you will get lucky and have those gears mine for years, you could and probably will be very disappointed.

Ok, that's fair enough, but it's based on the assumption that difficulty only goes up if gears became more effienct, which isn't entirely true, the difficulty will go up as long as there is profit to be made by someone, somewhere, it's even worse as many miners don't make profits and keep on adding gears.


I agree.


By the way, I by no means think that difficulty will keep going up 100% every year, just the same as I don't think price will go up every year, I also don't claim that this model is accurate, but the general idea of difficulty doubling while btc price only goes up 50% isn't at all a bad model to use when doing the math before investing in mining.

What most people do is underestimate the difficulty and price effect on their ROI, and given the fact that once your gear is no longer profitable it will have little to no resale value, ROI should be the main focus, so the average joe goes to Whattomine (or even worse Nicehash that displays wrong income) and work with the numbers as they are, and they see 6 months ROI, compare that to any other business on planet earth and it's a no brainer, so they go all in, some even borrow money hopping to return it in 6 months.

So by applying a simple model like this one, if the calculator shows 100$ a month, you should assume that by next month it will be 5$ less as a result of the difficulty alone, and assuming the price isn't going to go anywhere, and then you have to compare that against buying bitcoin, because if you invest $600 in a gear that makes

$100 in month 1
$95   in month 2
$90   in month 3
$85   in month 4
$80   in month 5
$75   in month 6
------------------
** 5% increase in difficulty won't yield these numbers, but this is a rough estimate using numbers that are easy to work with.

At this stage, you only have $525 + all the time and efforts wasted on running the gear, and as the difficulty keeps going up, it will eventually catch you with your pants down and gets you to the point where you can't profitably mine with that gear, this assumes the difficulty gets you before the chip thermal paste or the PSU does. 

So then, for those who like the fiat related math, they should actually not use the 50% increase in price which OP projects, just assume that your income will drop by at least 5% a month, the price will not go in either direction and your gear will die in 12-16 months, if using these figures doesn't bring up an interesting result then you are likely better off buying the coin directly or saving your money under the pillow.

Then you should only allow S9s to mine to your pool because I can't find the source code for S11, T11, S15, all of the 17 and 19 series, if publishing a single version gives them the permission to not publish the rest, all these custom firmware devs can just publish one version for a given miner and keep the rest.

Give up Kano, Bitmain gears with the stock firmware do violate the GPLv3 license in the same manner that all of these custom devs do and yet you are fine with allowing them to use your pool, it's just easier to deny that than having to admit that you are cherry-picking who to "fight".