Topic: ANTMINER S7 is available at bitmaintech.com with 4.86TH/s, 0.25J/GH - page 64. (Read 528055 times)

Awesome test - I only tested on 120V at 60% fan and EVGA G2 which shows 1440W+ depending on FAN speeds.   Can you do the same test for 700MHZ with FAN speed of 70% and 731M?  This is good info when we need to download clock or OC.

i see you are new but they did this with all of their miners. keep in mind the s7 wont be for sale forever and the value will probably be worth more after the sales run out. just look at the s3 and s5, still selling well after they have been discontinued.

Very nice nhando, great idea to reduce cooling cost if I ever want to get a place with industrial electricity rate.

Test on Batch 8 with dps-2000bb at 240v and fans at 40%

600mhz: 1130watt

650mhz: 1230watt

700mhz: 1320watt

http://imgur.com/a/sOO1z

I got the same results on another test & same results confirmed by a friend

To get back on point.  For those that are prepping in advance to battle the Spring / Summer heat.  I found these 2 methods very effective.   Very cost effective for larger deployment.  You don't have to have a fancy setup, the more sealed the environment, the more effective at creating the negative pressure.  I even test just funneling horizontally and it works fine.   .  Hot air rises so the solution below is the most effective.  I have an Exhaust fan (recommended by MarkAZ) sucking up the hot air.  It can easily pull down the Temp by 20-30C as you're pulling all the heat out quickly.  The heat wall prevent the hot air from recycling back.  Without the heat wall, you will lose about 10C+ of cooling easily and you will need a much higher CFM fan then a sealed solution with a cheap foam board heat wall.

Method 1:  Funnel all the hot air to a Plenum, or tunnel to outside or thru the ceiling / attic.   I connect the FAN to my WEMO insight, so I can set rules to only have it run during the hot hours and turn off during the cool period to save energy.   The fan works so well with the funnel, I don't even have to put it on Max speed, only on low or off still is fine as the miner's exhaust fan can do a lot of pushing.






Method 2 - For small setup.
Use these 3D printed ducts, connect to Exhaust and intake fan.  You can either just blow out the hot air or the best is to take in outside air and blow out hot air outside.  This will have no impact on your house temperature as it's all recycling from the outside air.  You can actually put acoustic foam around the dryer duct to help reduce noise level as well.  This solution works for all 120MM fans, so you can reuse them even after upgrading your miners.  Works amazingly well as you no longer worry about overheating your room or pulling out all the AC air. 

Next difficulty will not be as nice.  I'm riding on a ton of equipment right now but by purchasing over different time period helps the dollar cost averaging.  Your free Electricity help soften the next difficult blows as cost for electricity will be almost 50% of the total income in 1.5 days.  In a month Electricity cost will be higher than 50%, etc.  Let's hope BTC rise above $450 soon and that will help soften the blows.  This is really a fun hobby / business so I hope it remains profitable for many years to come so we can all enjoy it. 

you should not blame Bitmain for your decision to buy overpriced miners and not being able to predict reaslistic ROI times
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Well, when the s7 came out, it was not overpriced. Hence, I did not buy an overpriced miner, given the timeframe. It only became an overpriced miner when bitmain decided to sell the same unit for half the price less than 3 months later. And yes, I can blame bitmain for poisoning the resale well, because no one who bought a miner when the s7 first came out would have ever thought that bitmain would lower the same price on the same miner to half in less than 3 months.

Who would want to buy an s7 at my breakeven price? I can't sell it for a breakeven price on ebay if I wanted to, because bitmain is selling a brand new unit for less on their own website, with a brand new warranty. Do you see my frustration now?

And when it comes to predicting realistic ROI time, who could have predicted the bitcoin network would jump from 471 petahashes on november 11th, to 1,066 petahashes as of today (less than 3 months later)?

To give you an idea on the massive increase in hashing power in 3 months alone, on April 29th, 2014, the bitcoin network had 57 petahashes. On that same date in 2015, the network was at 340 petahashes - it took an entire year to gain slightly less than 300 petahashes in power.

Fast forward to August 8th, 2015 - the network was at 377 petahashes.

less than 5 months later, we are almost triple that.

Between the bitcoin whitepaper coming out in 2008, until August 8th, 2015... it took 7 years to get to 377 petahashes. And we tripled all of the hashing power that took 7 years to build, less than 5 months after that point.

So you tell me how someone could accurately predict something like that?

Ja that has been an immense help. No debating that!  
Still, as a few min ago, after deducting electric cost of $0.15/kW/hr (nice that my pool lets me enter that into the dashboard) each s7b8 at home is still paying out $4.83 per day so money is still to be made for home miners. Just not as much as fast. If ya wanna go big you have to live in the right place or at least move the farm to a commercial/industrial location for lower electric rates.

edit: as an additional offset, the 7.3kw of heat the miners at home produce means that my furnace has rarely turned on this winter despite temps down to the single digits. Still paying for the the heat but the BTC income just offsets my usual bills for the furnace...

IF you don't have free electricity and if you buy into the system now. Simple math, even Bitmain Fanboys have to admit.

If I remember correctly, you also got free electricity right?  Second biggest cost next to the miner investment is electricity, so you're definitely way ahead of the game compared to the average miners.  If you have free Electricity, it's very hard to lose in this game as you can hold on to inefficient miners while others have to pay premium to stay in the game. 

Meh.. I mean I see where you are coming from, but there is still money to be made if you do it smart. At least that is what I've experienced. I guess everyone's experience will vary to some degree based on the nature of Bitcoin.

I too have been getting s7's mainly to increase my farm hash rate while staying under my power budget.

ROI depends on how you look at it. They are paid for out of the total farm BTC income. I haven't paid with fiat (~8k$) since April 2014. I've bought scads of miners, 2x TV's, 3x PC's, 5x UPS's, and more with the BTC earned and still have a sizeable BTC kitty left over even after ordering 2 more s7's a few days ago.

So, just how is mining after the GPU days now for "suckers"?

yep

don't forget that at the same time they reduced number of chips thus making miners less efficient yet no one seems to care and still buys them a ton

No but really, Bitmain did a pretty good "fleecing" on this one!

Bitmain used to sell their miners with a 3-4month payback window (estimated).  With the S7 all of a sudden it was 6+months?  But we still bought em! 

Then of course instead of the 5-6% growth rate required to actually ROI all that goes out the window with a little BTC/$ spike and Bitmain dropping the price to 50% so they can just keep selling!  Then doulbe digit increases again.  Brilliant!

At this point when I bought the S7 I did it mostly to lower my power costs over the SP20/S5, but I knew it probably would never ROI.  Mining has pretty much been for "suckers" past the GPU days.

I received my B9, it was packaged exactly the same as the B8, it appear unused or at least clean, smelling fresh of the factory with no visible use or damage.

Performance wise, as expected, but much better efficiency, i don't know what to say about this;

cant agree enough. the advent of <0.3w/gh combined with bitcoin price going from 250->$450 was obvious kindling for a massive difficulty spike.

if anything, its best to buy miners just slightly after the peak of a price bubble whent he exponential difficulty growth begins to slow down once more (ie: around now, perhaps holding out for $400/BTC first)

you should not blame Bitmain for your decision to buy overpriced miners and not being able to predict reaslistic ROI times

At the current price, newcomers will have faster ROI despite the higher difficulty but the problem is Bitmain itself doesn't care about their customers who bought right away when they launched S7. Things are a lot better pre-S7 days when you can ROI in 8 months or so with S5s.

True- but maybe keep one rig to play with.

Well I think they're trying to move as much stock as possible before the BitFury chip comes on line. True- Bitfury rigs will go in their own Data centre. However, they are also selling chips soon. I saw one of their ads pop up on one of the sites i visit. So you might expect to see BitFury's own Data centre take a fair leap in hashing power and around June or July someone will be selling rigs built with the BitFury chip. It may be too late to buy one of those ?. However, I think Bitmain is wanting to get as much as possible out of the S7 before then. Also, i would think Bitmain is prepping to bring a new chip of their own to market by this summer to compete with the BitFury chip. Guess we will see.