Well... I for one appreciate Kano watching out for the pool in order to make sure the members get all the shares they deserve.  Few other pool administrators do that, fewer still have any idea HOW to do that.

Kano really REALLY doesn't like repeating himself.  He did state in his original response that you were the only one running the unknown firmware.

From observation:  I can state that all current S9s, T9s, etc. from Bitmain and all Avalon 821 & 841s (and I suspect earlier versions but those were before my time here) are supported since they behave as expected.

Given the problems Slushpool recently had, and that they are one of the ASICboost pools, I'm left wondering if there is a coorelation?  Therefore VERY happy that Kano is as protective as he is.  Am sorry that it affected you personally.

I'm earning about $1/day/841 after I subtract my electrical cost (about $0.08/kwh).

Just taking an educated guess, but I suspect by "firmware" Kano is referring to the version of cgminer your hardware is using.  e.g.  The manufacturer modified cgminer somehow.  

From Kano's response, it sounds like modified cgminer software has been known to cause problems to pools in the past (block stealing, bad stats, etc.).

Thus he isn't banning you as a personal thing, but rather not allowing your hardware on the pool to protect the pool and its other users.   This feels similar to me to the ban of rental equipment he has in place (Nicehash specifically, plus some others)

Agreed.  My whole datacenter is wired based on (2) miners per 20amp 220V circuit.

You used 250 cfm/miner, recommend 300 cfm.

What does the wattage based math I outlined tell you?

Evaporative cooling, presuming water is cheap, would be a good option.  Yahoo does this on some of their data centers.

Would also suggest bumping that air flow.  I run my datacenter based on 300 cfm/miner (combined flow between the 2 fans) and it works out reasonably well.

Congratulations!  Your using an industrial miner in an office environment and wondering how to make it more quiet.

This is a topic any search would find dozens of hits on, suggest doing so if you don't like my short answer:

Your screwed, and noise is the least of your problems.  Your running 5 space heaters in a closet that require in total about 1500 cfm of fresh cool air to keep from overheating. 

You need to THINK about what your doing and run some highschool math.

is this a new miner from Bitmain or something you bought elsewhere?  Almost sounds like somebody changed the root password.

Try SSHing in via something like Putty and see if the real root password works:  root/admin

Just showing the math:

Current hashrate is about 35,000 PH, or 35,000,000 TH. 

Blocks per week is (on average) 6*24*7  = 1008

So chances for a single 13.5TH miner to find a block in a week is 13.5*1008/35,000,000 is 0.0003888 or 1 in 2572.

Choose your own estimate for future hashrate.

Good news:  Power in == heat generated, so it really doesn't matter if your using GPUs or ASICs.

Using an S9 as a rough basis point, 1450Ws needs about 300 CFM of air for cooling.  So just figure your wattage and use that ratio to get close.

So just wildly curious... how do you propose to determine who the bottom 50% are?  By the pool they mine on?  No pool is over 50%...

Exclude the top pools?  That would be BTC at 22%, Antpool at 13.4% (35.4% total), ViaBTC at 11.7% (47.1% total), and about a 1/3rd of F2Pool users (how to pick which third?)?

Who would be the percentage cop?

Do you really think you could get such a proposal passed knowning it would penalize half of the population relative to the other half?

Exclude by destination address?  No problem, I'll create 150 accounts with one S9 per account...  automating such things is pretty trivial (ask Storj, where folks had 1200+ at one point because they wanted to favor the little guys).

Your going to have to override some defaults and reduce memory usage.  I would suggest you look at:

-maxmempool (defaults to 300MB)
-dbcache (defaults to 450MB)

Presumably your blockchain is being stored on an external USB 2.0 disk drive, since you would eat your SDHC card alive with activity.

If you are VERY VERY confident in your firewall, anti-virus, anti-malware, and you promise to encrypt your wallet - the Bitcoin Core 0.16.0 wallet works fine on Windows.  Biggest risk is keylogger malware that could capture your pass phrase.  Here is a link to decent "health check" instructions for windows 7: https://answers.microsoft.com/en-us/windows/forum/windows_7-security/how-can-i-remove-keylogger-issues/495a304e-b910-4b8e-8593-834307c590b1?db=5

Remember that you need 187GB of free space to store the full blockchain currently, and that will take a couple of days to download.

The hardest thing for any electrical gear to deal with, other than heat, is power cycleing.  When you power down, the fans stop running, and heat builds up briefly until natural convection eliminates it.

The net result is that you should expect most problems to show up after a power cycling event.  In this case, it appears you have a hash card failing.  You can try rebooting or power cycling it again and cross your fingers, but if it is persistant, the card needs to be repaired or replaced.

Don't mind at all.  Actually, have 20 of them - just about what we expect in a month.

Lets just do a quick sanity check on the 1% statement:

Total electrical power consumption globally in 2012 was 20,900 TWHs, with a claim that was up 5% by 2014 (21,945 TWH) per Wikipedia.  Charts from https://yearbook.enerdata.net seem to confirm a number in that range. 

Lets use Bitcoin as a basis for hashing.  Its hashrate is approximately 40 EH (40,000,000 TH) or about 3 million S9 13.5TH miners.  Round an S9 up in power consumption to 1500 Watts/hr to cover some incidentals like building lights.  So 1 miner uses 1.5KWh*24*365/yr or 13.1MWH per year.   3 Million of those would be 39 TWHs.  Bitcoin represents about 40% of global mining, so call it an even 100 TWHs for all mining.

1% of 21,954 TWHs is 219... so mining perhaps uses 0.5%.  Actually closer to 1% than I figured it would work out too.

Note this presume all serious amounts of mining of Bitcoin are used with S9 or better technology, since that has been around for a couple of years now.

So far, besides the normal red lights (better, faster, cheaper from a company nobody has heard about - posted by newbie accounts), I've seen 2 other red flags:

1)  Someone Google imaged search one of the executives and found an exact match for a guy in Odessa, Urkraine with a different name.  Faking photos is not something a legitamate company would do.

2)  The other thread on this in this section is self moderated and HIGHLY edited.  Ask about demo units for review purposes and your post gets deleted.

I have a whole flock working on the problem (yeah, I really do live on a farm...):

Let me respond slightly differently:

Every "profit switching" pool I know of (and I helped support one for a few years) basically looks at the current exchange rate and coin difficulty to determine which is the most profitable at the time.  What they CAN NOT do is predict what will be the most profitable at the time any found block is matured enough to sell the proceeds.  Using Bitcoin as an example, if you find a block you can not spend that block for an additional 100 confirms.  At 10 minutes each that is about 16.7 hours into the future.  Sites like http://fork.lol will help you visualize this - pick any point on that graph, then look 17 or so hours into the future to see if it was right...

What is worse, especially for alt coins, is that few, if any, profit switching pools look at the order depth for the coin.  Thus a coin may LOOK more profitable, but if you attempted to sell a block rewards worth, you might flood the marketspace.  Hang out on an exchange like Poloniex sometime and see just how shallow most market spaces are.

So to be really accurate, you would need TWO crystal balls that can tell the future...  shy of that, your just guessing.  How does the saying go?  "Past performance is not indicitive of future results".  Required wording on all financial statements in the USA.