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Delivery

26-Jun-18:

UPS delivered! Driver still thought VAT needed to be paid but was happy with the ref numbers given - keep your numbers handy for the knock at the door.
Didn't have time to unwrap today.

Set-up

27-Jun-18:

Ubnoxed and all looking good except for a tear in the antistatic wrap on the miner, apparently from a rushed packaging job.
APW3 PSU lines all come out of the same terminals so clearly no difference between them, I plugged four into the Z9.
Powered up and let it run through its routine. Fans went to max temporarily which is pretty damn loud, even default speed is noisy enough, no idea how I'm going to keep three of them quiet at home.
Ran through the admin pages of the Z9, all self explanatory except 'Advanced > Frequency: 500M' which can be set from 100M to 750M. I left it at the default for now, I assume this is for overclocking which voids warranty.
The three pool settings are all to antpoool.com and mining to a Bitmain address of course so first things first, switch to accounts I own.

For now I'm using a mobile SPV wallet until I get my full node running properly. I will be making regular transfers to a cold address from the mining address.

I went for the following pools in this order:

• NanoPool
  • stratum+tcp://zec-eu1.nanopool.org:6666
• FlyPool
  • stratum+tcp://eu1-zcash.flypool.org:3333
• SlushPool
  • stratum+tcp://eu.zec.slushpool.com:4444

Easy peasy - seems to work fine, now just let it run. ASICs really are easy, the maintenance is far lower than with GPU rigs, just blow the dust off from time to time.

I soon realised NanoPool wasn't working properly, I had earned only ZEC 0.00000220 after 2 hours. I switched to FlyPool to make sure the problem wasn't my end. FlyPool results started to match the profitability calculator after after enough data had been gathered.

Overclocking

28-Jun-18:

A kindly reddit user informed me that overclocking to 15 kSol/s is possible. Heading over to the ZCash Forum there are plenty of other Z9 owners doing the same. Given that the option is there in the UI (Miner Config > Advanced > Frequency); that others are doing the same with successful results so far; and that winning at the mining game means being early... I decided to boost the power and noise too and take the risk of a shortened life span and voided warranty.

I overclocked step by step, 500M, 550M, 600M, etc so as not to push my luck. I ran each stage for at least half an hour to let the metrics stabilise. I ran for a day and half at 700M, and then on the 02-Jul-18 increased to 725M.

Here is the data:

Frequency (M)	Ksol/s(Avg)	Ksol/s(%)	Temp PCB	Tmp PCB(%)	Temp CHIP	Tmp CHIP(%)	Fan 1	Fan 1(%)	Power(w)	Power(%)
500	10.96	100%	44.000	100%	56.333	100%	2880	100%	260	100%
550	11.83	108%	46.667	106%	60.000	107%	3120	108%	290	112%
600	13.08	119%	45.667	104%	59.667	106%	3120	108%	313	120%
700	15.14	138%	49.333	112%	63.333	112%	3600	125%	368	142%
725	15.64	143%	51.333	117%	65.667	117%	3840	133%	383	147%

The power scales up linearly with the Frequency, but nicely, so does the hashing power (Sol/s) - the Z9 retains it's efficiency at overclocked speeds. The extra heat is also dealt with well, the fan speeds up enough to keep the chips cool. They do heat up, but at less of a rate than the hashing output so in a 'solutions per degree Celsius' way, the efficiency actually improves by overclocking.

I have read that Antminer S9 temps are often in the 70-80C range, and some quote around 100C during summer months. Being below 70C seems well within the safe zone for the Z9 Mini.

ASIC distribution

02-Jul-18:

How about the competition? How many miners are out there and how early in the queue was I? I am aware of the following batches sold so far, though Bitmain don't make it easy to keep track of this data:

• Batch 1:

  • $1999
  • Available: 03-May-18 13:34 to 20-Jun-18 12:44 UTC (last sold unit)
  • Scheduled Shipping Date: "June 20-30th"

• Batch 2 - Part 1:

  • $1520
  • Available: 15-May-18 09:20 UTC to ?? (my estimate based on sales spike, bitcoin talk and twitter)
  • Scheduled Shipping Date: "August 24th- Sep.4th"

• Batch 2 - Part 2:

  • $850
  • Available: 05-Jun-18 to ongoing
  • Scheduled Shipping Date: "August 24th- Sep.4th"
  • Edit: I previously called this Batch 3 but that seems to diverge from Bitmain's naming convention which seems to focus more on shipping date than price.

I've collated all of the shipping data from Bitmain published via Twitter using the hashtag #Z9QA. It seems this only covers Batch 1 so far, meaning they are yet to ship any orders from Batch 2 (parts 1 and 2). Bitmain announced that the data published so far only relates to the batches estimated for shipping "June 20th-30th". Looking at the data, indeed my orders from 7th June ($850 per unit) are not included.
We have to take Bitmain's word for this data, there is no real way to verify it. Interestingly, my purchase date and time (as stated on the order email Bitmain sent me), never appears in their official list which indicates there may be extra orders not mentioned in the public data. Please comment below if your exact purchase date and time also did not appear in the published lists.

The shipping dates of each order aren't published either so I've assumed 4 days after twitter announcement as that's what it was for my order.

• 7,742 units purchased in total (from the "Jun 20-30th" batch)
• 50% of the run sold in under 48 hours.
• First order was within 10mins of the first Twitter announcement (assuming Bitmain sales data is in Beijing time, GMT+8hrs)
• Interest waned rapidly after the first 2 weeks, with the bulk in the first 3 days only.
• Shipping completed over a brief 7 day period (plus 1 day for the 77 units which went out much earlier than the rest), about 1,100 units per day on average.
• A second spike in sales on the 15th May following the price cut from $1999 to $1520. This means the two batches overlapped, and buyers had a choice of paying $1999 for a June unit, or $1520 for an August unit.
• $15,476,258 revenue for Bitmain from Batch 1
• There are still all of the units to account for from Batch 2 but these will not have been shipped yet so expect the difficulty to rise another 40% if batch sizes are similar.
• None of this accounts for the Innosilicon ASICs.

If mining is all about being early, newcomers will have to have their wits about them to complete with the pros who have been through this before. Get your bitcoins ready for payment and watch announcement like a hawk. Never-the-less, I got in the first half of the first batch so hopefully still stand a chance of making some kind of revenue (though profit remains doubtful).

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Next post: Revenue data, pool switching and updated forecasts, in part 4.