As Philipma said, is one of the main reasons I stopped using Bitmain miners after batch-25 of the s9 series. Just too many hash boards dying. Up to the s9 they were much much more reliable.

Switched to the Avalon's starting with a couple 721's and never looked back. Out of several dozen of the Avalon miners over the years only 1 failure and that was the fan on 741 - which even after 2 years Canaan replaced no-charge. These days it seems that the PSU's are the main failure area und ja, Bitmain has the same issue (along with other problem areas) as do the Whatminers.

So ya want to lug around a 20kg battery to be able to mine for what, maybe 15min at best?
Ya would work with some USB sticks but any miner pulling over 100w or so is a definite no-go...

Nope - can't do that. It's a type of software license key. ANY firmware that uses the DEVfee model requires that it can periodically  'phone home', in this case to get the DEVfee work and send back the results. If the connection is blocked the miner stops working until the connection is reestablished.

As OS2sam said, read the top post. Full install instructions are here
on page 3 of this thread.

Ja your main problem is the old copy of cgminer as it does not have the driver (which Kano wrote) for the chip the F uses. His official git with his most recent update for it is here. In that update he also cleaned up code for the earlier Compacs as well as a few general cgminer bits.

It should just be a simple RasPi display application that runs on another thread. Poke around the various RasPi Maker sites for the display boards and the code to have an app periodically query the cgminer API (that Kano wrote) to get the data you want to display.

btw: Kano is now the sole active developer for cgminer since -ck long ago closed his cgminer thread and locked his cgminer git. The most current repository is Kano's. Along with writing the CompacF driver and adding it he also cleaned up a lot of other code and drivers while he did it  

^^ remember that the max current per-pair of USB ports in each row of a Gekko hub is 6A so having 2 sticks on 1 pair with each pulling 3A or more will make the regulator for that pair of ports shut down and then hopefully restart again. My stick is pulling a safe 2.85A @ 575MHz so when I eventually get a 2nd I'd still be good with 2 in a row.

eeeehhh yes and no.... I assume that is a large value cap in parallel with the bank of lower value caps right? Ja the ASIC chip may still be operating because the DC is 'reasonably clean and good enough' but it would be interesting to probe there and at the chips power pads to look at the switching spikes with and w/o that cap...

It is far too common for power supply designers that want to feed high current/high speed digital circuits to neglect the fact that chip switching speeds are deep into the RF spectrum making the DC power planes feeding them a transmission line. The end result is that as the gates inside of the chip switch the signal and DC power voltages at the chip pins can/will be quite different than what you probe and see as you get away from the chip.

Point is ya should verify the at the chip itself that the Vcore referenced to its return pads along with the data eyes into/out of the chip look solid even without the cap.  Neglecting that is one of the things that back in early 2014 killed Bitmine.ch's Coincraft miner which used their A1 chip that they paid Innosilicon to design and work with a Foundry(TSMC) to source. Well, that and totally neglecting the fact that that you also need sizeable heat sinks on top of the ASIC's... The folks that did things right used the same A1 chip in their legendary Dragon miners had great success with them...

3-phase supply is *mostly* irrelevant as all miners use single phase power. Where 3-phase does come into play is if you use phase-to-neutral connections for breaking out the power, you MUST ensure the resulting voltage is between 208-240VAC and in most countries your phase-to-neutral voltage will either be too high or too low.

DaveF summed it up in general terms quite nicely.

The difference is that a FPGA is of course Programmable. In a nutshell that it means that the signal pathways between the synthesized sha256 cores and the I2C coms can never be optimized for the most direct & shortest path to give highest possible speed because each logic element used to synthesize the sha cores has to go through the programmable connection logic elements (called a switch fabric) used to create the logic structure for each 'core'. Once programmed, cycle-for-cycle a FPGA does its processing exactly the same as an ASIC does but has a lot more circuitry and signal path length to contend with which slows them down considerably.

That said, FPGA's are used to test new iterations of an ASIC's logic gate structures that make up its sha256 cores before committing any new design ideas to silicon.

At best the performance would be akin to using a Foundry's library of pre-designed 'standard' logic cells that are routed willy-nilliy to standard com cells to make a mining chip: It works but because the I/O pathways cannot be changed to minimize the physical lengths of the connections between the cells you end up with slower speeds than a full custom ASIC can give.

Of course in a FPGA those programmable connection pathway elements also require power whereas ASIC's don't have that circuitry so the ASIC has better power eff and the die real estate that would have been used by the connection elements is just filled with more cores... Not sure how many cores even the best FPGA could emulate but for reference each Bitfury 14nm chip used in the Apollo miner has 4096 cores in it and that chip is certainly not cutting much less bleeding-edge tech. AFAIK the latest chips from Bitmain and Canaan have over 8k cores in each one.

Bitmain, Canaan, Bitfury et al custom laid out the physical cells and their interconnects 'by hand' to get the performance they achieve.

Same way your phone/pc talks to here -- majik! 

Could well be using some of the Bitmain or MicroBT 5nm chips same as Sidehack uses 7nm in his CompacF. The Apollo uses Bitfury chips.

I highly doubt they could have come up with the >8million $ it costs for the litho masks alone much less design costs + Foundry production costs to roll their own.

You mean the threaded brass standoff's like these?

Folks, it should go without saying that considering this person is brand new here and is already spamming a few different areas with their sales ad -- BUYER BEWARE!
They and their company have ZERO history here so until a few folks that are known and trusted here can vouchsafe for them -- BEWARE!

Folks, it should go without saying that considering this person is brand new here and is already spamming a few different areas with their sales ad -- BUYER BEWARE!
They and their company have ZERO history here so until a few folks that are known and trusted here can vouchsafe for them -- BEWARE!

Folks, it should go without saying that considering this person is brand new here and is already spamming a few different areas with their sales ad -- BUYER BEWARE!
They and their company have ZERO history here so until a few folks that are known and trusted here can vouchsafe for them -- BEWARE!

All 'they gain' is the primitive, idiotic, self-centered satisfaction stroking of their ego as they attempt to control other people. At least the Taliban can use (their interpretation of) religion as justification. The folks this topic is about do not even have that going for them  

No you CANNOT!

Thermal grease and pastes are NOT adhesives. Ja they are tacky but they will not hold for very long plus without some sort of mechanical clamping they will eventually start to lift off.

Well, I suppose yes you can as long as the miner is laid on on its side with the heatsinks facing up... In any other orientation gravity is going to do its thing and in fairly short order the sinks are going to slide & drop off...

You have posed a very vague question. Outages how often? How good is the power when it is on?

If power outages are a very frequent thing then you need to get power that is not tied to your grid. eg solar, wind, small scale hydro etc.

If outages are common but not a regular thing then one has to ask how stable is the power when it is on? Miners MUST have a stable incoming voltage typically between 208-240VAC. Prolonged operation below or above that range will quickly kill the miners.

There is no question of 'those coins are real or not'. What part of it being impossible for additional coins to be injected into the BTC blockchain other than by mining and getting the block reward do you not understand?

The fixed amount of new BTC being produced on average every 10 minutes are 'minted' by 1 way and ONLY 1 way - by actual mining and being the 1st to get a block. The network itself produces them by a fixed set of rules. No other way exists for coins to enter the blockchain so banks or any other entity cannot just 'print' BTC. Period. End of story. Nothing to see here...

What folks here are trying to get across is that other than as a purely academic exercise, hashing sha256 just using CPU(s) has no possible use. Even the most primitive ASIC sha256 chips from say late 2013 delivered speeds in excess of 1GHs when pushed hard and over 500MHs when throttled back. Even a very high-end PC with 24 or more cores cannot match those early generation mining chips. What you are looking to do is like learning assembler (lowest level CPU microcode) vs learning a interpreted programming language. Ja, it is always nice to know it or at least have a decent understanding of it but overall aside from some very specialized purposes not helpful to know.

Point is that any real world application of sha256 blockchain technology is going to use ASIC's - not any mid to high level interpreted CPU code like C, .NET, Py, etc running on CPU's. Even the most modest applications would at least use FPGA's or even GPU's vs CPU's. The fact that Intel jumped into the fray with their open-to-all-comers mining ASIC proves that.

Now, if you want to explore how to talk to an ASIC mining chip might I suggest you checkout Kano's cgminer git and pickup a low cost USB stick like any of Sidehack's to run the software on? Compiling instructions are here.

Being fully open source you can not only see and tinker with how the software that interfaces between the BTC network and a miner operates but also investigate the code used as drivers that interface between software and the actual ASIC chips. The driver library also includes one for FPGA's as well as a variety of ASIC's.  That is the side of your learning that has useful career possibilities.

Edited for typo's