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We are new to mining, but have been monitoring since Dec'15. We're prepared to purchase S7-LN as it came with power supply so it seems like a good purchase. However, S7-LN recently went out of stock.

We're looking to purchase S7s now and considering PSUs for our S7s. Should i get PSU from bitmain, or should i go with other PSUs like EVGA Supernova 1600?

first question do you have  220/240 volt power?

you should not get bitmaintech  or evga 1600 if you have 220/240 volt power

read this thread  far better to use this system to power s-7's and or s-9's


https://bitcointalk.org/index.php?topic=1373092.0;all

https://bitcointalk.org/index.php?topic=1373092.msg15403344#msg15403344

Hi philip, thanks for the great information. We're indeed running on 240 volts. I'm not too sure of what is that thread about after i read it. From what i understand it is regarding breakout boards. Does that mean that we'll require breakout boards to run on 240 volts?

Thank you!

It's advertising a server PSU and breakout board which is, overall, better than Bitmain's PSU. The conversion efficiency is a few percent lower but the total power, reliability, flexibility and price beat it.

If you're in the US and wanting to buy S7 from Bitmain, I can probably hook you up with undervolted units that run 85% hashrate at under 70% power versus stock units, with a power supply, for about the same price you can get just a new S7 shipped from Bitmain. This makes 'em more efficient than an S7-LN and can also be run on 120V.

I've read the post again.. Is the PSUs mentions DPS2000BB ?

Also, why would we need the breakout board in addition to the PSU?

I'm actually located in Southeast Asia, Thank you for the offer though  ;)

Most of the PSU's I use in my farm are Bitmains, have 26 of them and with the oldest ones being almost 2 years old so far zero problems.

I also have used the IBM DPS-2000 w/ breakout boards (needed because the PSU has no wires coming out of it), also very good and yes a bit cheaper than Bitmain's PSU's but it does a take a bit of time and effort to get everything together (PSU, breakout, PCIe cables) whereas Bitmains are totally plug-and-play.

Based on your location and parts availability you are best off with bitmaintech.

If you were USA based I would say go with the dps-2000 and set up that way.

But  your location means the bitmaintech psu is easier.

Sidehack's  modded s-7's and his power supply is also really good, but once again cross shipping  China to usa to asia is an issue.


Why do want s-7's do you have cheap power?

The S7-LN seem to come in and go out of stock on BitMain, they might be back.  Did you check the Hardward for sale here, I saw yesterday sidehack had a modded S7-LN for sale.

He's also got  a few modded S7's for sale.  Better than ordering directly from BitMain.  https://bitcointalk.org/index.php?topic=1556664.0

I am actually not very good in electronics, so i guess i will be going with bitmaintechs PSU. Im afraid that i might mess up on breakout boards  :D


Thanks philipma, i will go with your recommendation!

And Yes, we actually have very cheap power. The USD/TH for s7 makes more sense to us as compared to s9. We decided to go for S7-LN as it came with power supply, but it went out of stock. Rang bitmain up yesterday and they told me to wait till next week for news if S7-LN will be coming again.

I realized that the power supply for s7-ln is only 1000w, and cant power s7/s9 and thus i decided to go for s7 instead.

Another thing, i'd like to thank you and NotFuzzyWarm as i have learnt alot in the forums from you guys!


Bitmain told me over the phone to wait for news on S7-LN next week. They might come up with a new batch. But i have heard from some users that they are clearing the old power suppliers from S2, so they came up with S7-LN. we shall see next week if they will come up with a new batch

I purchased a total of 15 S7LN from Bitmain and got three bad power supplies. I was able to fix one of them but 20% failure rate is not impressive. I could tell several of the working supplies had also been opened up and worked on before they ever got to me.

A good PSU breakout board is pretty much foolproof. A lot of them nowdays have the same power jacks as the miner will, so to mess up cabling is almost impossible. Just plug everything together (it'll only go one way), flip the switch and you're on.

Hi.

I run in the UK at 230 volt.
I have never purchased a Bitmain PSU. I started using IBM Server Power Supplies a couple of years ago on my Spondoolises SP20's.
I carried these over to the S7's and the S9's.
Just two pins to solder together to get the PSU to run up and I use 1/4" Lucar Crimps to connect the wires onto the PSU.
I use two per miner, both rated at 1300W, they are DPS-1300 PSU's and have always been reliable for me.

https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2F3YfHs4w.jpg&t=566&c=Ck25dXn1-L2bWA

PCIe jacks on the breakouts may make things easy BUT I'll take your terminal strip and cables with spade lugs any day. Since the PCIe plugs/jacks are the weak point in the power chain, losing one set is great.

One thing that needs mentioning is that these connectors have a mating-cycle rating and most of the time it is surprisingly a low number: often just several 10's up to maybe few hundred at best.... Each time they are plugged/unplugged the connector gripping tension becomes weaker and plating is scraped off of the pins eventually leading to increasing contact resistance/heating/failure.

Thanks for the update. I guess i'm glad that i didnt go with S7 - LN.


I think that it is not economic if we were to use 2 PSU to 1 miner, unless you already have the PSU. is that right? For eg : 2 power supply rated 1000w = $200 each. 1 power supply rated 2000w = $300 each.


That sounds complicated. Can i ask what is the difference between PSU + breakout board and PSU from bitmain?

What is a mating-cycle rating? Did a search on google for those terms and understood a little, but didnt get the last paragraph.

Hi MineRonnie.

I buy ALL the power supplies from eBay, generally from computer recyclers.
I have never paid more than £15 for a Power Supply, normally around £12 to £14 each.
That makes a pair of power supplies max £30.00.

The IBM 1300W power supplies are very reliable and although I have one which is a little noisy on start up, they just run really reliable.
Just eBay search for IBM 1300W and you should recognise them.
If you look at my photo with the power strip at the bottom, solder bottom LH and the pin directly above it.
Power supply just runs straight up on power up.

Have fun!

I'll toss in my 2c - I never skimp on buying PSU's.  Of all the things you'll be buying when you're mining, PSU's are probably the only thing that will last your mining lifetime, and be the same value when you sell it as when you bought it (assuming we're talking server PSU's with breakouts).  There are several great breakouts - the ones I've used and really like are Optimizer's and Sidehacks (Gekkoscience), they're both on the top end in terms of quality and workmanship.  Oh, and don't skimp on power cables either - 16 AWG all the way and you'll never have any problems.

It is how many times a connector can be plugged and unplugged. Google gave this as top search, http://www.cirris.com/learning-center/product-articles/other-products/227-connector-life-cycles and it pretty much describes it in detail.

As for the effects of wear, as the metal plating wears off and/or the contacts begin to loosen contact resistance goes up. That leads to the connector pins heating up which starts to increases oxidation, which in turn increases resistance, etc. It's a vicious cycle.

240V Ac in SEA ::)  malaysia? singapore? or brunai?

few months ago i tried to search for those used server DELL/IBM psu but the price +shipping is way too expensive :( 

you better order Bitman PSU directly from https://shop.bitmain.com/productDetail.htm?pid=000201505040743496917U7kGsCm0694

usd140 + shipping usd30 total usd170 with 12 month warranty.

Thanks flameruk, that's a very good suggestion BTW, to buy used PSUs at such price is worth considering. However, after some searching on eBay, it costs around 120USD for 2 PSUs + Shipping. With that, i think i'd go for bitmain's PSU as they come with 1 year warranty too. What do you think?


That is what im considering too. Miners come and go, but PSUs will be used again and again.


Oh, i apologize for not finding that and thanks for the explaination.


Location shall be kept a secret until one day we're ready to open up to hosting  :P

i agree with your calculations too. But im afraid that bitmain's PSU would breakdown easily, and from what i gather from forums, their warranty takes a loooong looooong time.

https://www.bitmaintech.com/productDetail.htm?pid=00020160725071342525Njtyqt6h071C

I see. They came up with a second batch. However, the PSUs only have 90day warranty. What are your thoughts about that?

If you're looking for another alternative, I offer IBM 2880W PSU's with breakout boards and cables, they are being used to power 2x S9's or S7's without any drama.  Plus, if you ever do develop PSU problems, the boards and cables are re-useable.  Shipping PSU's to you from North America would be very expensive, but if you can find a cheap supply of the IBM 2880's (model AA23920L) in your area, send me a PM and we can work out pricing on boards and cables.  I have supplied many mines and data centres with PSU's that are plug & play (unlike some server PSU's that require modification),  my customers have been very pleased with the product.

Good luck

Hi MiningRonnie.

Looks like the Server PSU's are expensive in your part of the world.
I just ordered two more for £19.00 the pair from eBay with free shipping!

If you get stuck I can see if I can source in the UK and ship over to you, just a thought.

The APW3 vs other non-bitmain PSU debate is something I've been mulling over. As of right now i've got 4 APW3's working great, all are putting out 12.23~ volts. I've ordered a 2000 watt IBM blade center PSU ($30 refurb) and a breakout board kit with cables from holybitcoin. Costs me $60 less than ordering APW3 from china, I'll report back my findings once everything comes in  ;D

Never had issues with bitmain's PSU.... running 408v 3 phase 220v single phase... all connections running stable on all miners... then again we do have power factor correction and stable voltage 24x7x365...

I have not had any issue's with APW3's.  They are what Bitmain recommends with S7/S9.   I personally have followed this and not had any issues on the PSU side.  They have kept working for quite a while now on some as I sold S7's and kept the APW3's.    They can power even the batch 1 S9's which had the highest hashrate's.

There will always be market of server PSU's with breakout boards out there.  But until I have a problem I will keep using APW3's as far as S9's at this point.   I am not knocking some of kit's out there as I have not tested them.   So just making clear not knocking them just saying what has worked good for me.

At this point a lot of my ATX psu's I had laying around from previous gen miner's went to mining Ether.   I have had a decent variety of PSU's over the year's.  If you have the 205V+ it is the one I would go for.    If under the 205V then I would look at the EVGA Supernova 1600 you mention, as EVGA does have some great highend PSU's.

Hey Finksy, that looks like a very good alternative. Was actually looking at a 1600W PSU for 300USD, with 5 years local warranty. Hard decision for me. I'm actually leaning towards 5 years local warranty, due to the reason that i'm not sure whether PSUs breakdown easily, and their usual life span after being used. What do you think?


Hey buddy, thanks for the great offer! I'll actually consider that. What PSU are you actually talking about for 19pounds a pair?


Great! Will be waiting for your findings then. Which PSU to use is actually a big decision for me  :-\


Did a google search on power factor correction. Is that something that helps on saving electricity? Do you mind explaining how it works? Thank you!


Thanks for your input. Can i ask how long have you been using those APW3s? The reason why im afraid to use APW3s is because i'm afraid that it would breakdown after the warranty expires.

I actually have 240V over here. I'm actually leaning towards APW3s now after hearing your input. Decisions...

I've been using Bitmains PSU's for over 2 years now. Currently have 24 of them running s7's and s9's 24x7x365 with most in 85-90F ambient, zero problems. Frankly, I love them. Pure plug and play with miners.

Sounds good. If i were to use other PSUs, isn't it plug and play too? Since there is no configuration for PSUs.

Since the launch of S7's, at that time I decided to use APW3's and so far I have not regretted it.   They should last long after warranty if you have the luck I have had.  A LOT of these psu's are out there and there are many user's.    Also I figure Bitmain themself use them in internal mining facilities.... I don't think they would use them if big problems.

So I don't think you will regret decision as long as you have 205V+ and use a proper power cord.  You do provide your own cord for the APW3's as there are so many different options depending on setup/pdu/etc.

I see. If that's the case, i think i should be getting APW3. As for power cord, is there any difference for power cords? I always thought that power cords are all the same.

I was referring to the various server PSU setups where you need a PSU, breakout board and leads vs ready-to-run.
And yes I also have several of the IBM 2kw's and several HP-DP1200 PSU's using breakout boards. all work fine.

<facepalm>
The PSU end of the power cord is a standard IEC-13 connector. The wall end.... depends on what country you are in. There are a lot of flavors for the >200v plugs.

To be honest, there's good and there's good enough.  In my eyes, mining is still a business, so keeping costs in check is important.  Why pay $300 for a PSU when $120 for Bitmain's (or $85 in the case of my IBM 2880W PSU's) will do the same job adequately and reliably? The more you spend on PSU's, the less you are able to spend on miners, plain and simple. Anyone that tells you otherwise either has constraints limiting their choices (<200V AC input or require SATA/ATX plugs for motherboard), has made a hobby of it and wants to show off their bling, or are delusional. The only other factor to take into consideration is PSU efficiency, and if at your given electricity rate the extra cost for a more efficient PSU is worthwhile in the longrun.

The wall end also can depend a lot also worth mentioning a lot will change based on what PDU you use (assuming you use one).  Not all PDU's use the same connector going into them so it's worth looking at when buying a PDU.   I personally have PDUs between miners and wall in all 240 connection's I have.  

It is worth noting you can find some decent to great deals on PDU's on ebay from time to time.  I owe phil for one he told me about once.   But if your ever in market for PDU check ebay a lot as it tends to change on what is best deal.

Ahh.. i think i understand. Apologies for not being a technical guy  :(


True that. I guess i'll be going for bitmain's PSU. Thank you!


Can i ask what benefits does PDU provides? Do we need them?

I will be honest some of your questions are a little scary to me.   Is this something your wiring yourself? Or is wiring already there if so take a picture of plug and we can say more.  

What a PDU does is allow you to run one cable with a lot of amp's to power multiple miner's.  This varies on your voltage and number of amps on which PDU is right for you if any, there are a lot of different options. But basically your PDU plug's into your power outlet and basically split's it where you can power multiple miner's from it (assuming power is there).   *Edit   Better description then mine I think is here - https://en.wikipedia.org/wiki/Power_distribution_unit

+1

PDU's essentially act as portable sub-panels by providing circuit protection to individual PSU's/miners, eliminating the amount of electrical circuits you need in total, and giving you flexibility in powering miners.  Also, if you are hiring an electrician (which I strongly suggest you do) you save considerably on labour and likely materials by running fewer, high amperage circuits to your mining area.

to chime in quality  used pdus on eBay for 50 usd  are easy to find.

this is a 30 amp version  it should be able to run 4  apw3-12-1600 psus

http://www.ebay.com/itm/30-amp-8-outlet-PDU-With-Twist-lock-Plug-/251702276381?


so

fuse box with a 30amp 240 volt fuse>>>>>>>> 30 amp 240 volt wall socket that matches the pdu plug>>>>>>pdu>>>4 separate psu's

Hire someone that knows how to do this. This can kill you if you do a bad DIY!!!

+1

PDU's matter for those who wish to run more than one or two high powered miners. Once you decide to run more than one or two S7\S9's you really need to think about how to run power to the devices safely and efficiently while also taking into consideration the number of slots open on your electrical panel.

Initially i started off with a NEMA 6-20R Leviton 5824 20 Amp, 250 Volt, duplex receptacle which allowed me to power two S7\S9 off of one circuit. In my electrical sub-panel, i have a total of three (dipole) spaces. If i used a single duplex receptacle per circuit i could only hook up a total of 6 miners (2 per circuit).

However, by using a different receptacle and adding a PDU i was able to connect four miners per circuit giving myself 12 total connections on the same space in the panel. I ended up settling on using a NEMA L6-30P Leviton 2620 30 Amp receptacle since it is a fairly common connection for PDUs. I also went with a Tripp Lite PDUH30HV19, was a little more expensive, but it fit the bill.

...As mentioned previously, none of this really matters unless you're trying to plan for running several of these high powered machines...

I do understand that PDUs distributes power. But i suppose that we're good to go, since we installed 1 plug point for each miners. Isn't that so?

Why would we need PDUs, since we can just install one plug point per miner? Is there something im missing out?

It sounds like you are good to go for your current setup! The only reason you would need a PDU is if you want more miners and you dont have enough space in your main electrical panel to wire in another plug. Is that making a little bit more sense?

so  you want to do

30 amp
fuse  in box..................plug in wall..........plug in wall........... plug in wall......... plug in wall...........plug in wall.......plug in wall


correct?  so 3x 2 plug  receptacles  are 38 bucks

6 special power cables are 90 bucks  that is 128 dollars.

you need 3 wallplates and 3 boxes for the walls as I for one would not put all into a 3 gang box.  so 10 -15 more.

so 153 in parts.  no extra fuse protection offered by the pdu.

but i do not know full code for your area.



I am usa based    so   code for above  is this receptacle  wait for link

https://www.amazon.com/Leviton-5822-W-Receptacle-Commercial-Grounding/dp/B000U3I1S0

now see photo  below  12.72 for one  which does 2 plugs

if you do a 30 amp fuse at the box  and buy 3 of these  you could do 5 s-9's   at full speed   or 6 s-9's with a down clock.


https://www.amazon.com/NEMA-6-20P-C13-Power-Cord/dp/B004WJNVH4/ref=sr_1_1?



https://i.imgur.com/VFftnsR.png


https://i.imgur.com/ZyNZhmX.png

Thank you very much for the explaination!


Does that mean that PDUs is much more cost effective as compared to plugging it directly to the wall?

I think you are missing out on the reason for the PDU.  If you had a wall plug for each psu (with proper voltage and amps) you would not need a PDU.  This is more common in say 110-120 volt.   But a PDU allows you to take one big power source (via the outlet) and distribute it to many item's.   For example say you have 240 30 amp running to your miner's most likely you will need a PDU to take it from the outlet to your PSU's.

It's more about being a necessity in some setup's then the cost aspect.  But you could save money running 1 wire to it vs many lower volt/amp wires (but this could very).

I suggest reading post before:

I finally understand it now.. So it is much safe to be using a PDU as compared to running it from the outlet.

1. PDU offers extra protection
2. save cost as you would only require 1 outlet from wall as compared to lots of outlet installed.

More or less, yes that is correct. If you plan correctly and get all the right equipment, you can safely plug multiple miners into one wall receptacle via a PDU. Keep in mind, the most important part of this whole thing is planning properly.

You need to know:
-amperage rating for your current electrical panel
-how many unused spaces in your electrical panel
-how many miners you want to add within the next 12-24 months

Once you have these facts laid out in front its easier to plan and easier to get usable advice.

how much each hash board consume in S7 & S9 ?
S9 1200W for all controller and hash board
so how much I/O controller need from this 1200W