PSUs are on average 3% more efficient on voltages above 200V compared to 120V.
Yes that one specific item is more efficient at higher voltage. It is probably one of the very few items, and only is because it is designed to work on both voltages. Items that are designed to work with 120v are the same efficiency. This whole sub topic suggests changing the entire wiring system in the us to 200v+. From an efficiency standpoint this is hard to justify for a 3% difference in one appliance.
This doesnīt even include higher losses through wires at 120V vs higher voltages.
This is the negligible difference that I mentioned. Most household circuits draw less than 6 amps. The resistive loss in the wire is barely noticeable.
Differences in safety are marginal (and probably nearly nonexistant), how do you get in trouble with "safety" on properly connected wires anyway?
It should be clear that the breakers should be switched off when you do any kind of maintenance on your wiring and open appliances....
Differences in safety are far from marginal. Most electrocutions happen between a hot conductor and ground. In the European system you have almost twice the potential voltage. Everyone knows that you should disconnect power before servicing wiring and appliances. Yet somehow people (including children) by the thousands get electrocuted each year. If wall outlets all were fed with 240V you'd have the lower current and higher power advantage of the European system and it would be safer too, since each "hot" would still be only 120V from ground (not 240V) which keeps the reduced shock hazard advantage. This even suggests that the 240V system would be safer if installed properly. The usa 240v system is safer, However if everything in the us was converted to 240, it would be 240v to ground, why would we install an additional conductor and buss bar for everything, just to be safe when the system we have works fine. If that is correct then why didn't Europe do it that way? For applications that need more power we have a similar system to Europe with 277v to ground 480v across phases. |
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They will not fix that as it makes the gov and monopolistic utilities too much money. Do you happen to know the reason why all US is using stupid 120V circuits?
They've got Thomas Edison to thank for that. He wanted lots and lots and lots of local power stations all supplying low voltage DC, where as Westinghouse wanted big power stations delivering high voltage AC. But why? What could be the explanation? And why aren't they changing those rules that are over 100 years old? It doesn't need fixed. Safety is the reason. Only a few applications make sense to supply more than 240v. I have worked on electric motors that are 9600v. This system is flexible to meet requirements while keeping safety in mind. Thomas Edison lost that battle, how is he relevant? The power plant has nothing to do with residential voltage. Our power plant makes 347,000v. |
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Pls, this is totally offtopic, anyone is grateful to tesla but please not on the spondoolies thread.
It hurts both my eyes and my hand when I need to scroll down for hours....
Agreed
120V is inefficient and has greater losses (on virtually any appliance), but Americans arenīt known for their overly logical approach to many issues, so yeah.
the efficiency difference between 120v and 208/220/240 does exist, but is hardly worth mentioning. As far as logic goes, I think the reason is very logical. 120v 240v(split phase) 208v (3 phase) is safer than 220 single phase. A insignificant loss in efficiency for increased safety, seems logical to me. While still having the 240v available for higher demand loads but in a safer way than europe adds versatility.
If you are planning on installing some new circuits in your hosting site, better make them 208V or 230V ones, as to give your miner the maximum performance (and save some additional % on electricity).
Absolutely, but not for the reasons you mention. My main consideration would be more power over the same wire. Less material and labor for the same kw. |
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With the 25% difficulty jump, hopefully the price goes down soon!
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The R9 290s are sold, I still have some r9 270x cards and rigs for sale. The link below has a picture of one of my frames with some 6950 cards in it. I don't have any 6950 rigs left, but I have 4 cards. I also have some corsair tx850 power supplies. I will sell anything so let me know if you want a rig, card, frame etc.
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Did you find out if you can give a better price without a powersupply?
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still have these? current asking price?
Yes they are still available. Asking price is still at $400. I think that price is fair, they are still selling for 450 -500 on ebay, but if you would like to make an offer pm me and I will consider it. |
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i believe for 6gpu in scrypt you'll need more than 8gb ram.
I run 6x 270x with win7, ubuntu and bamt with 4gb, and have verified they still work with 2gb. the 290s are roughly twice the speed, so i would guess that 4x the minimum would suffice. I intended to build a 290 rig but haven't unboxed the gpus yet, and i am not going to loose the value of them by opening them just to verify ram, but I assume that 8gb would be fine. |
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On all of my setups I have the dps2000bb powering the pcie connectors and the 12v wire for the riser card. The 5v line goes to a hd connector on the psu running the motherboard, and both grounds are tied together at the riser connection. No problems whatsoever.
Yep, that will work just fine. Connecting negative terminals between power supplies will not hurt anything, most of the time they are all ready bonded together anyway. They are bonded to ground in the power supply and all of the ground are connected together in the electrical panel. All of the positive connections are isolated in the card. |
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If it's a linear regulator shifting 5V down to 3.3V, running 12V into it is going to increase the power dissipation (and therefore heat) by five times. If it is indeed designed to give you 3A at 3.3V, it's dissipating 5W from a 5V source and that would be 26W from a 12V source - likely enough to explode it. I'm kinda surprised they didn't put a switching regulator on there instead, which is common for anything expecting to pull more than 1.5A or so.
My boards give you 5V rated for 2A; the circuit should handle 3A output.
Other manufactures may be different, I have two different types of usb risers. One has a linear regulator and the other I cannot find a data sheet for, but I would guess it is a linear also. I also doubt the card pulls the full 10w at 3.3v. I will measure it when I get a minute. You also can't assume that the riser board is designed to deliver all 10w. I thought you "shouldnt mix" PSU´s when powering a GFX. EX.: PSU 1 - MB + 1 GFX PCI-e & Riser (by riser i mean the 4 pin molex)PSU 2 - GFX PCI-e & Riser 2, 3, etc, etc..... From what i read, it seams that mixing and matching PSU´s will cause undesired efects (Burn baby Burn)  Or am i just getting this wrong ??  I can confirm with 100% certainty you can use a server power supply to provide the power for the 6pin connections and the motherboard power supply to power the slots. I have built alot of machines this way. All of the power connections are isolated inside the card. You should never directly connect 2 power supplies together, unless they have a current share pin and it is connected correctly. I used a 650 watt supply to run the motherboard and the risers for 5 cards. When I added one more it wouldn't run. I switched to an 850watt for 6 cards and works great. I use a 1570w dell supply to run the 6pin connectors |
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If it's a linear regulator shifting 5V down to 3.3V, running 12V into it is going to increase the power dissipation (and therefore heat) by five times. If it is indeed designed to give you 3A at 3.3V, it's dissipating 5W from a 5V source and that would be 26W from a 12V source - likely enough to explode it. I'm kinda surprised they didn't put a switching regulator on there instead, which is common for anything expecting to pull more than 1.5A or so.
My boards give you 5V rated for 2A; the circuit should handle 3A output.
Other manufactures may be different, I have two different types of usb risers. One has a linear regulator and the other I cannot find a data sheet for, but I would guess it is a linear also. I also doubt the card pulls the full 10w at 3.3v. I will measure it when I get a minute. You also can't assume that the riser board is designed to deliver all 10w. |
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Hi, At the expence of sounding like a newbee, i am a bit at a loss. After browsing trough the comments, i am still trying to figure out where to get the 3.3V line from on the DPS-2000BB. AFAIK, pci-e slot draws 12v and 3.3v. I am using the USB RISERS - https://www.hashratestore.com/shop/cables/usb-pcie-riser-powered-molex-60-cm . Apart from the standard pci-e 6 AND 6/8 PIN SETUP (12V), it also uses 4 pin molex which carries 12v G G 5v. However, according to this: Except for a potential maximum 10W from the PCIe +3.3V slot, all remaining power consumption will be on a +12V output.there should be 3.3v comming from the molex and there isnt. I can only conclude that instead of 3.3v it uses the 5v from the molex in the same way. The PCIe X16 slot supplies 75W of which 10W comes from the +3.3V output (3.0A)The following questions comes to my mind: 1 - How many WATT/AMP can i pull from the DPS-2000BB 5V line ?? 2 - If not, can i use a molex from PSU powering the RIGS ? I do apologize in advance if this has been covered before. Cheers, Mac It uses a voltage regulator to make 3.3v. ok, do you mean the usb-pcie-riser uses a voltage regulator ? That would mean i would use the molex as follows: 12v G G 12V instead of 12V G G 5V and the riser does the rest. Or do i need to adapt one to get the 3.3v from the 12v line ? Cheers, Mac Yes, the usb riser has a regulator on the 16x board that plugs into the bottom of the power supply. I do not know right off of my head if it converts the 5v to 3.3 or the 12v to 3.3 but logic would tell me it uses the 5v, otherwise it would probably get really hot. You would need to look at the regulator and make sure that it can accept 12v input and then see how hot it gets if you feed it with 12v. The regulator is going to dissipate almost 3x the watts that the card uses at 3.3v if you feed it with 12v, so it may only work for a little while, then burn out the regulator. looking at my usb riser right now - yes the 5V is used, and is connected to the flat 3-pin chip, presumably to drop down to 3.3V as mentioned. putting 12V through that is a TERRIBLE idea. It might sound like terrible idea, however, after looking at the data sheet, i found that max input current is in fact 12V. It does get quite hot though. Considering that u only connect the GFX cards to a single PSU, and the the 12V line is not an option, where do i get a 5V or a 3.3V line from if not supplied by the PSU ? You could use the connections from the power supply that powers the motherboard to power the risers |
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Hi, At the expence of sounding like a newbee, i am a bit at a loss. After browsing trough the comments, i am still trying to figure out where to get the 3.3V line from on the DPS-2000BB. AFAIK, pci-e slot draws 12v and 3.3v. I am using the USB RISERS - https://www.hashratestore.com/shop/cables/usb-pcie-riser-powered-molex-60-cm . Apart from the standard pci-e 6 AND 6/8 PIN SETUP (12V), it also uses 4 pin molex which carries 12v G G 5v. However, according to this: Except for a potential maximum 10W from the PCIe +3.3V slot, all remaining power consumption will be on a +12V output.there should be 3.3v comming from the molex and there isnt. I can only conclude that instead of 3.3v it uses the 5v from the molex in the same way. The PCIe X16 slot supplies 75W of which 10W comes from the +3.3V output (3.0A)The following questions comes to my mind: 1 - How many WATT/AMP can i pull from the DPS-2000BB 5V line ?? 2 - If not, can i use a molex from PSU powering the RIGS ? I do apologize in advance if this has been covered before. Cheers, Mac It uses a voltage regulator to make 3.3v. ok, do you mean the usb-pcie-riser uses a voltage regulator ? That would mean i would use the molex as follows: 12v G G 12V instead of 12V G G 5V and the riser does the rest. Or do i need to adapt one to get the 3.3v from the 12v line ? Cheers, Mac Yes, the usb riser has a regulator on the 16x board that plugs into the bottom of the power supply. I do not know right off of my head if it converts the 5v to 3.3 or the 12v to 3.3 but logic would tell me it uses the 5v, otherwise it would probably get really hot. You would need to look at the regulator and make sure that it can accept 12v input and then see how hot it gets if you feed it with 12v. The regulator is going to dissipate almost 3x the watts that the card uses at 3.3v if you feed it with 12v, so it may only work for a little while, then burn out the regulator. |
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I get that there's a lot of negativity on here regarding this product but I am still curious and have some questions for solarminer.
What are the dimensions of the solar panels?
In your photos, the solar panels look like they would not do well getting wet regularly. Are your solar panels built to maintain constant outdoor conditions, or just temporary?
Can you do custom orders, e.g. Can I buy without your solar panels, then connect my own?
Can the power source transition from solar/battery to mains automatically. If not; could I leave the unit plugged into a mains connected timer (set to deliver power to the device only during some nighttime hours)?
There is alot of negativity about these because we understand solar power and realize that this product is an absolute waste of money. |
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Hi, At the expence of sounding like a newbee, i am a bit at a loss. After browsing trough the comments, i am still trying to figure out where to get the 3.3V line from on the DPS-2000BB. AFAIK, pci-e slot draws 12v and 3.3v. I am using the USB RISERS - https://www.hashratestore.com/shop/cables/usb-pcie-riser-powered-molex-60-cm . Apart from the standard pci-e 6 AND 6/8 PIN SETUP (12V), it also uses 4 pin molex which carries 12v G G 5v. However, according to this: Except for a potential maximum 10W from the PCIe +3.3V slot, all remaining power consumption will be on a +12V output.there should be 3.3v comming from the molex and there isnt. I can only conclude that instead of 3.3v it uses the 5v from the molex in the same way. The PCIe X16 slot supplies 75W of which 10W comes from the +3.3V output (3.0A)The following questions comes to my mind: 1 - How many WATT/AMP can i pull from the DPS-2000BB 5V line ?? 2 - If not, can i use a molex from PSU powering the RIGS ? I do apologize in advance if this has been covered before. Cheers, Mac It uses a voltage regulator to make 3.3v. |
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For that kind of money I would buy a used 6970/50. You can find them around 100 bucks and get 470khs out of them pretty easy.
If warranty is what you are worried about XFX is lifetime, but they are known for using cheaper components(not necessarily that they fail easily but they don't overclock as well)
Also, takes me back. Ever played duck tales? I remember our second computer was so fast (cyrix 100mhz cpu) that you couldn't see the hook spinning on the rope.
you must have some 6970's sent from heaven to do 470khs I'm able to get 450khs on an ASUS 6950 unlocked and oc'ed but never hit 470 I use all different brands and achieve the same result. 6950 shader unlocked or 6970 =470khs 6950 standard 430khs I even get these rates on the extra cheap visiontek 1gb $169 refurbs (they have been running solid for a year now and I got over half of them to unlock) and yes they came from heaven(newegg) |
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Didn't you all know.. IF you can not make a 5 million dollar purchase, "Buzzman" has no love for ya. Stopped buying Bitfurys and started buying antMiners 3 months ago. SOOO happy I got in on the S2's (AKA Bitfury killer). As for the bitfury's, they have been delegated to the test lab for now and soon the rifle range. CEX.IO has 2 Petahash worth of "futures" going for less then $5/GH not likely Megabigplower will ever have anything to offer miners. Lucky for him noobies like Merlin are born everyday, how's that 5 million in Bitfury gear treating ya?
All of these giants buying all of the hardware and mfg making huge mines is not exacly in their own interest. Bitcoin has a future, but until it is established it is on ice. The reason many people get into it now is because of profit, either mining or trading, don't get me wrong, I said most. As a few gain control and hardware never profits then bitcoin will be forgotten. |
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For that kind of money I would buy a used 6970/50. You can find them around 100 bucks and get 470khs out of them pretty easy.
If warranty is what you are worried about XFX is lifetime, but they are known for using cheaper components(not necessarily that they fail easily but they don't overclock as well)
Also, takes me back. Ever played duck tales? I remember our second computer was so fast (cyrix 100mhz cpu) that you couldn't see the hook spinning on the rope.
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Post pictures with your username written on a piece of paper in front of them. Will you use escrow? These haven't been opened at all? escrow is not a problem, if you pay for the fees, and use someone we can mutually agree on. 5/6 are sealed. I opened one just to check it out. It was never installed and still has the protective film all over it. |
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