Bitcoin Forum

I see all kinds of prices on Ebay like well over $400, but given current state of things, that's kind of a lot...

I'm thinking that since price is looking good right now, and I have cheap electricity, ideally I didn't want to put more then $300 into one...

Any thoughts?

"Don't mine, it's a fool's game". Tbh, I just like the feeling of mining, and my electricity bills here aren't unbearable... Plus, if you get cheap hardware, in the longrun if you can front your electricity costs, the BTC you'll make, and their value in the longrun, could be much higher and your actual price/BTC may be lower in the end. Like I said, mining is just fun. When you're not having trouble...

What's the absolute max you'd pay for an SP20 nowadays?

Low 300's sound good. Anymore and you run the risk of it devaluating highly before you can make up the difference. On the other hand with the BTC price looking strong, it sound like a overall good deal if you can get it for 360$ shipped or less.

350 to 375 seems fair.  Assuming it works and that your power is not crazy high.

Alright guys, thanks. Yeah, I already have a bunch of PSU's lying around (from S3's)... I'm honestly thinking of selling them off in favor of SP20's... So much freakin' headache to have to run a crap ton of Antminers.

I do have a couple other questions and I hope you guys can help. Does the SP20 have built-in wireless? And if it does, is it less advanced than setting it up on an Ant? I don't mind either way because I'd have many less units, but just curious...

Secondly... I believe for 1.7 TH/s, you need to be supplying the unit with about 300 watts in each 6 pin slot... Suppose I were using a CX750m for two of those... Power-wise, the PSU can handle it I think... But the problem that concerns me is the 8 pin to 6+2 pin connectors. They kind of daisy chain two 6 pin connectors to that. Now, I know I would have to use each 8 pin independantly, because those two 6 pin connectors would want 600 watts, so that's out. And I guess the SP20 can adapt, but like I said, I want max hashrate...

If I take one 6 pin from each of the two 8 pin connectors, will that single 6 pin on each connector be able to give 300 watts to each slot? I hope what I'm saying makes sense...

I mean, I know for a fact that a single 8 pin to 2x 6+2 can power an Antminer S1, S3 etc with no overclock (though the wires get warm) Of course, each blade is only 130 watts, so it's a combined 360. Fine... What I'm asking is, can one of those 6 pin connectors be capable of delivering 300 watts on it's own through one of the connectors? My Rosewill Photon came with 8 pin to single 6+2 pin connector, as opposed to the double ones... Would that be required? We already know the 8 pin can supply the power... But is the single connector tough enough for that current? If both are daisy chained and all that current is running into one connector, then into the other, I would think maybe so... But I'm not sure.

Sorry for the novel... I just wanna make sure I'm equipt for getting these units only to have them sit and have to mess with things for too long. :/

First, ignore the +2 pins on both end, they're just extra grounds. Second, a double cable would work, the problem is it would probably heat, then melt, then maybe fry your stuff. I believe the safe level is 190w each for double. In this case you definitively will want to only plug one 6 pin per cable.

For the 6 pins @ 300watts, it depend on the connectors and the cables themselves. If its 16AWG it should be fine, you can easily find out by just touching it after its been running for few. If its hot, then its not good. Basically avoid 18AWG wires if you want to run 300watts in a connector.

Keep checking every other week because if it heat up, it may get worse and worse.

I've had bad cables work fine, warm, then hot, then melted after 1.5 years of 250watts each.

Last thing to keep in mind, if your PSU is pulling 1200watts at the wall, its not running 300watts per pci-e, since you need to deduct the watts wasted by the PSU conversion and also the fan's usage.

 Partly correct. The fan usage DOES come out of one or more of those PCI-E connectors (I think it's probably split between 2 of them, but haven't pulled my SP20 apart long enough to actually check it).


 DON'T count on 1.7 TH - you have to have a very cold room to even have a prayer of achieving that. 1.3-1.4 TH range is achieveable easily even in somewhat warm rooms though, and is quite a bit more efficient to achieve.

 Do NOT under any circumstances try to run 2 connectors from one cable, unless it is a VERY custom cable with something on the order of 12AWG wiring.

 SP20 does not have wireless. Standard twisted-pair Ethernet only.

 The official spec on the MOLEX connectors that the PCI-E power specification uses works out to 288 watts per connector (the pins are rated more, but have to derate for use in that particular connector style).
 Exceeding this tends to lead to issues like the KnC Neptune and some Titans had with MELTED connectors and resultant fire and damage-to-unit risk.

 Most power supplies use 18AWG on their PCI-E connections - this is plenty for a SINGLE connector at 225 watts (per the PCI-E spec), it gets a bit marginal at 288 watts.

I wonder, what is the highlighted based on?
I run Sp20E very downclocked at ~1200Gh using ~640-650W at the wall from a single Corsair CX750M, which has 2 split PCIE cords providing 4 required connectors.
The cords or connectors never exceeded 45C and I have a lazer temperature probe.
I grant you that you have to first connect a more powerful PSU (like EVGA 1300) or two CX750, then change settings on the machine to downclock, check power usage, achieve stable hash and then optionally changeover to a single CX750, but it is doable. I run a machine like this for almost 9 mo with no problems whatsoever.

I'm doing the same thing.  I have been running underclocked for quite a while now.  It just made sense.  The 1.7 I don't care how cold you won't get this.  

But for everyone except "free" electricity it makes much more sense to underclock you make more BTC mining this way on SP20 Jackson.  I have never had issues with PCIe cable's.  But I have had nice PSU's on my miners and always been careful.

Thats fine, good double cables at 650*0.9=585/4=146.25watts per connector, well in the 190w per connector's limit for doubles. Op was talking about running effectively twice the power through the same setup.

@Quint, The PSU has a fan, and it does not go down PCI-e connectors. Also for the ASIC's their consumption is also lower at the machine than at the wall. Not that it changes much.

I sold a few days ago, my last SP20 for 1.65BTC+ shipping costs to Portugal.

Dats like a lotta' money though... :/



Also to you guys who were talking about wiring the unit up... My Photon 1200 did come with 2   8 pin to single 6+2, as well as the more typical 8 to double 6+2...

Suppose I grabbed a couple more of these for the other PSU's (CX750m) for example. With a good thick wire gauge 8 pin to single 6+2 connector, could that cable give the 300 watts? I think the main issue is wire gauge here, is it not? Obviously the 8 pin can supply 360 watts, I know that. But to supply almost that much through a single connector, I'd imagine I want it to be a pretty damn high quality cable.

Wait, though... On the 8 to 2x 6 pin, does the electricity not travel through the cable, to the first connector, then jump off to the other connector?

So in theory, could just plugging in one of the two connectors handle that flow, if it is all initially flowing through the first connector regardless? If I'm not making sense, I'm sorry. I'm crap at articulating things.. :/

It's a lot of money to mess around with PSU's.  Get a proper PSU with enough PCIe cables if you want too run twords it's higher side.  Most of us with them have them underclocked as honestly they make more if paying for electricity.

But mixing PSU's is not a great idea most that do use the same PSU and 2x of them.  If separate hashing boards.... 2 different cheap psu's just looking for trouble.   But the honest anwser is get a nice PSU  and it will last multiple miners.  

Well if it has available slots, it will work. But it being a 8 pins does not change anything, the extra 2 wires are grounds, and ignored completely here. And an actual 300 watts is probably a bit much, but as i tried to say, you won't actually be feeding 300 watts.

And i say again, it will work, but it has to be very good connectors to handle it over a long period of time and we can't tell you that. I do not know how a SP20 will handle multiple PSU with slightly different voltage input.

The best might be running the SP20 on the single PSU at 1000w~ at the wall, if its rated 1200.

With all the s7 starting to ship, price will get down a bit more cause all the ppl will offer their sp20, so that they can upgrade!

Depends also where you leave, Europe add 2x% for VAT

 I would not pay more than $300 all-up for a SP20 at this time, and would be hesitant at more than $250.

 Even that would depend on my geting moved VERY soon to a very cheap electric-rate location (which isn't happening as soon as I hoped).

I wish you would use actual pricing instead of " I would not pay more than".  Look at ebay lots of sales but it is going to be mid to high 300's to 400 as a general idea.

Miner's do not sell for what we wish they would sale.  They have a cetain value.  If you did the " I would not pay more than" at your prices you would have no miners.

To be fair, Ebay prices tend to be fairly much higher than face to face and our marketplace's prices. I found SP20's for 300$, so i would not pay more than that, especially since we can get S5's for 250$ now.

Its a hard pick between S5's and SP20's around this price. I went with S5's for efficiency and $/GH.

That is why I like ebay on selling my old miners. I normally hit it up as it has a lot more customers bidding then on the forum it seems.

Although if it's a part unit I have had better luck on this forum.  So it really depends on what it is.  Each place has it's higher selling items, and lower selling items.

Yeah Ebay has all the oblivious people buying crap like 440MH/s usb stick for 40$. Then they come here and ask why they arent getting millions of dollars worth of bitcoin per minute.

Last time it was a guy telling i was a liar because i told him his 2 400mh miners and couples of r9 280x would cost him tons and return nothing. Apparently he was "making good money, you liar!".

The point is that right now its a sellers market when it comes to miners.

Mining is very profitable right now with the low difficulty and high BTC price, so nobody is selling.

Hence if you really want a miner, you will have to pay a premium

Low difficulty, high price? Are you smoking something?

Price is in the toilet right now (although going up a little) and low or high difficulty is subjective right now. I wasn't "low" since early 2014.

Any new unit (S7 for example) cannot break even at current price. Of course you can gamble and front your electricity costs and invest, knowing BTC will go up... But right now, you cannot mine for profit fast or cheaply enough to break even, so I don't know what you're getting at.

I think he means low difficulty jumps.  It has been much lower then a lot of us thought it would be on difficulty changes.

For those who are profitable at 230..... 270 is great for us.  So many miners are having a good time.  But I agree it is sellers market.   I want to repeat I have noting against QuintLeo, after looking at some posts I'm afraid it might take that since posts  don't have a tone to them like a talking conversation does.

I just found his should buy price, to be lower then actual market price.   And I realize that is my opinion.

 As it happens, I haven't bought any miners for a while - as I see ZERO chance of anything current achieving RoI before the halfing and pretty much NOTHING current except perhaps the S7 for a short while will be profitable at all after tha halfing, per my current projections.

 If actual pricing is higher than I am willing to pay to achieve a REASONABLE CHANCE OF ROI, that just means most of the market isn't doing projections of RoI based on what I class as reasonable projections, or possibly some folks have a TON better electric rates than I have - or the most likely cause, inertia leading to failure to adjust pricing to what is really fair by current standards.


 There is nothing new about "market pricing" being higher than reasonable. or price adjustments being slow to respond to external changes, or a market going with "optimism for the future" instead of paying attention to current conditions.
 Try watching the Dow Jones over the last 5 years - crazy high levels of stock price increases while the economy as a whole is barely recovering from the Great Recession and most corporations are NOT actually doing all that much better overall.


 Mining right now is lower profit than it pretty much has ever been, BTC pricing has been edging up lately but NOT enough to match recent difficulty increases - and the only reason diff increases haven't been higher for the last month I suspect to be the shipping delays BitMain has been having on the already-sold S7s.



 Your opinion may vary. Do not fold, spindle, or mutilate. etc.

With your current pricing in mind I don't think your purchasing  will change in the near future.  I don't see miners fitting in your ROI very often with current prices on rigs.

I think we have greatly different way's to obtain what value of miners.   I like market vs should be priced.  If it was should be I would have a bunch more S7's.  But they did not meet my ROI for largscale so I did not go crazy.

So I guess we look at most of it different but have a little common ground.

The price IS good. I think people tend to compare it to the MtGox bubble, not understanding that the value was artificially inflated by displaying fake transactions. As such overall, this is a great time to mine, where i live, the cost of running a S5 is about 20%~26% of its revenue.

As such, SP20 at 300$ if it can be run at full speed would be a GREAT deal, without doubt. The difficulty does not seem to be jumping high and the price is slowly trickling up. The SP20 has also great volt control, so its possible to gain greater efficiency fairly easily, prolonging its lifetime.

Only thing is you will never find a SP20 that can do the 1.7T.  That number was to high they never should have advertised it.   So never count on that with SP20 but I would agree sp 20 holds a higher price then S5 in most cases.

It's ability to underclock is very good.  So I predict it remains higher price then S5.  The SP20 has versatility just like Avalon 4.1's.  Which being able to crank it up or down so much is a great feature to have.

SP20 should be counted as a 1.3-1.4TH miner, not a 1.7 - it's bloody RARE for one to achieve 1.7 unless you have VERY cold air to feed it.

 Outside of that, it IS overall a much better miner than the S5:

 Far more configurable, with built-in undervolting will be profitable at quite a bit higher network diff than the S5 can achieve without the use of rather pricy "special" adjustable power supplies that don't tend to be as efficient as common ATX "80Plus Gold" supplies.
 Can be pushed for somewhat higher hash rate abet at the cost of a bit worse efficiency than an S5.
 Much better temperature monitoring.


 I find the "auto-tune" stuff to be a minus, but some folks prefer it.
 Stick shift vs. automatic I guess.