Topic: Selling $100k+ 50ghs+ Bitcoin Mining Operation w/ 104x 6990s [CLOSED] - page 2. (Read 5450 times)
February 21, 2012, 09:35:04 AM
200 amps is typical here. Quebec has extremely cheap electricity.
February 21, 2012, 09:30:27 AM
Hmm guess it is different in different parts of the country. Around here natural gas is common for cooking, hot water, and heating. Really the only high current device most homes have is an AC. Maybe that has something to do with it. Nobody needs 100A for a heatpump though. 30A, 40A for a very large one maybe. Also heat pumps are horribly inefficient when winters are very cold so that would be the last place I would expect high current installs.
Interesting. I guess the combination of the extremely cold winters and cheap electricity has something to do with it. As far as the heat goes, I could certainly burn up 100A to heat my home in the winter here. It wouldn't be drawn full-time obviously, but if I wanted to match my gas furnace in BTU output, I'd need 97A @ 240V.If someone has a 200A panel no reason they can't run a large farm but it would make sense to drop some dedicated 240V, 30A circuits to avoid overloading rest of house breakers.
Of course. You'd run out of power in no time trying to do this. I run two 50A sub-panels. 
February 21, 2012, 08:55:57 AM
I would be interested in hosting these for you for a percentage. PM me if interested.
February 21, 2012, 08:38:30 AM
Eh? Most of the homes here have 200A panels by default (except for the very small or older homes). Many town homes and duplexes even have 200A service run to their panels. It's done in case someone wants to run electric heat. Go somewhere where the winter gets very cold... the homes are all wired. I'm running 45Ghash and I've still got a little over 100 amps (at 240V) to spare.
Hmm guess it is different in different parts of the country. Around here natural gas is common for cooking, hot water, and heating. Really the only high current device most homes have is an AC. Maybe that has something to do with it. Wouldn't expect to see many heatpumps (and thus high current mains) where winters get very cold because heat pump efficiency is dependent on outside air temp (lower air temp = less concentrated thermal energy to pump).
If someone has a 200A panel no reason they can't run a large farm but it would make sense to drop some dedicated 240V, 30A circuits to avoid overloading rest of house breakers.
February 21, 2012, 05:27:51 AM
PM'd you on the other forum. That's crazy!
February 20, 2012, 10:59:51 PM
yeah, sorry.. these should be about 12.5-13.5 amps each, 120v @ 1500-1600w. I think we were getting around 2.4 ghs per machine @ ~1600w.
If three 6990s are pulling 1500-1600W, the clocks/voltage used were horribly inefficient. 1000 watts should be no problem with the appropriate voltage and clocks.Nobody would consider putting them on house circuits.
The largest issue in a residence is mains current. Most homes don't have mains capable of more than 100 @ 240V = ~20KW continual load. You can get that upgraded to 150A to 200A but it tends to be pretty expensive. Setting up a 60A dedicated subpanel @ 240V and leaving the rest for house normal load mean you probably are limited to around 20 GH/s in most residences. Still more than do-able for the quarter lot ($25K for ~12.5GH/s).
Eh? Most of the homes here have 200A panels by default (except for the very small or older homes). Many town homes and duplexes even have 200A service run to their panels. It's done in case someone wants to run electric heat. Go somewhere where the winter gets very cold... the homes are all wired. I'm running 45Ghash and I've still got a little over 100 amps (at 240V) to spare.
February 20, 2012, 04:42:52 PM
Yeah... I guess it isn't so much about density, as it is about convincing the owner of the location to rent me the space and pay for the power at a decent rate. I'll have to sit on this one for a bit and run some numbers.
Unless you can find a former data center or something, getting the concentration of power you need could prove difficult. Sure, if you've got a giant house, you could put one machine in each room but then you have to deal with cooling and ventilation and trip hazards for the entire house. Ideally, you can get 400 amps coming off of one wall, where you can box them all up, cool them without cooling your entire building, and shoot the exhaust outside. Really, this probably won't make sense for anyone spending > $0.07/kwh.
Nobody would consider putting them on house circuits. A subpanel & dedicated circuits @ 240V makes it a lot more manageable. Even if you had them in multiple rooms you would need to look at running 1 (or more) dedicated high current circuits to each room. Cooling is less of an issue if you have a decent sized room. Just drop in a dedicated AC unit. They make split units up to 50K BTU.
The largest issue in a residence is mains current. Most homes don't have mains capable of more than 100 @ 240V = ~20KW continual load. You can get that upgraded to 150A to 200A but it tends to be pretty expensive. Setting up a 60A dedicated subpanel @ 240V and leaving the rest for house normal load mean you probably are limited to around 20 GH/s in most residences. Still more than do-able for the quarter lot ($25K for ~12.5GH/s).
February 20, 2012, 04:31:52 PM
I have the funds to take a lot off your hands if you decide to use multiple buyers at 25K or so but in that other thread you quoted 6990s at about $200 above market price for singles so not sure what your expectations really are.. In any case if you decide to split into a couple of large shipments I'll be standing by..
You're right.. I can't find any 6990s for sale at retail but I think the last price I paid was $700 a piece. I don't know if there is still a premium for them but 104 cards * $700 = $72.8k. So, there are really 2 components to this: 25 rigs, 29 extra 6990s + other hardware. The 29 cards might not be that hard to flip for $20k. ...The actual mining value for these card for mining only is low, many 5970 sold for 300$ a month ago and they are better than 6990, ... 5850-5870 130-170$ (375-450mhs)
I suggest you sell all of these ASAP before the price collapse another 100$. The new 7970 sell for less than 600$, has better resell value, higher efficiency and almost the same hash-rate.
February 19, 2012, 10:41:21 PM
Yeah... I guess it isn't so much about density, as it is about convincing the owner of the location to rent me the space and pay for the power at a decent rate. I'll have to sit on this one for a bit and run some numbers.
Unless you can find a former data center or something, getting the concentration of power you need could prove difficult. Sure, if you've got a giant house, you could put one machine in each room but then you have to deal with cooling and ventilation and trip hazards for the entire house. Ideally, you can get 400 amps coming off of one wall, where you can box them all up, cool them without cooling your entire building, and shoot the exhaust outside. Really, this probably won't make sense for anyone spending > $0.07/kwh.
However it has since been converted to office and warehouse space. I would need to find out whether the owner would mind it becoming a datacenter again 
I think the power here is $0.09/kwh before taxes and shit, so it probably wouldn't be the most ideal location in terms of time to recover cost - especially when running air conditioning to keep things working in the summer. I may have to pass on this one, damn my location's power rates
(Central Ohio) 
February 19, 2012, 10:32:02 PM
Bloom Energy can reduce your energy costs by 40%-60%. Works for Ebay at their San Jose campus.
https://bitcointalksearch.org/topic/cheaper-electricity-with-a-bloom-box-google-was-first-customer-63670
https://bitcointalksearch.org/topic/cheaper-electricity-with-a-bloom-box-google-was-first-customer-63670
February 19, 2012, 10:27:26 PM
Yeah... I guess it isn't so much about density, as it is about convincing the owner of the location to rent me the space and pay for the power at a decent rate. I'll have to sit on this one for a bit and run some numbers.
Unless you can find a former data center or something, getting the concentration of power you need could prove difficult. Sure, if you've got a giant house, you could put one machine in each room but then you have to deal with cooling and ventilation and trip hazards for the entire house. Ideally, you can get 400 amps coming off of one wall, where you can box them all up, cool them without cooling your entire building, and shoot the exhaust outside. Really, this probably won't make sense for anyone spending > $0.07/kwh.
February 19, 2012, 10:20:06 PM
I have the funds to take a lot off your hands if you decide to use multiple buyers at 25K or so but in that other thread you quoted 6990s at about $200 above market price for singles so not sure what your expectations really are.. In any case if you decide to split into a couple of large shipments I'll be standing by..
You're right.. I can't find any 6990s for sale at retail but I think the last price I paid was $700 a piece. I don't know if there is still a premium for them but 104 cards * $700 = $72.8k. So, there are really 2 components to this: 25 rigs, 29 extra 6990s + other hardware. The 29 cards might not be that hard to flip for $20k. In determining whether and how to split up the rigs, I'm considering how much of a hassle it's going to be to get them to the new owners. They're all in Tennessee now. Where are you?
February 19, 2012, 08:32:04 PM
I have the funds to take a lot off your hands if you decide to use multiple buyers at 25K or so but in that other thread you quoted 6990s at about $200 above market price for singles so not sure what your expectations really are.. In any case if you decide to split into a couple of large shipments I'll be standing by..
February 19, 2012, 08:22:49 PM
Unfortunately, the pic you saw of them all stacked together in the garage is a pic of them in their current form. They're all offline and will not be reassembled in to their mining form. If you could do a setup like the guy in the above video, they won't take up that much space. It all comes down to your available power density, cooling/ventilation setup.
Yeah... I guess it isn't so much about density, as it is about convincing the owner of the location to rent me the space and pay for the power at a decent rate. I'll have to sit on this one for a bit and run some numbers. February 19, 2012, 08:10:10 PM
Unfortunately, the pic you saw of them all stacked together in the garage is a pic of them in their current form. They're all offline and will not be reassembled in to their mining form. If you could do a setup like the guy in the above video, they won't take up that much space. It all comes down to your available power density, cooling/ventilation setup.
February 19, 2012, 07:53:58 PM
Out of interest, any pics of the existing systems in their current form? I am particularly interested in whatever cooling arrangement you currently have. I have access to some used 10 ton CRAC units, and about 600 amps of 480 VAC, but I can't really get my head around how much physical space this might take up.
February 19, 2012, 02:01:54 PM
yeah, sorry.. these should be about 12.5-13.5 amps each, 120v @ 1500-1600w. I think we were getting around 2.4 ghs per machine @ ~1600w.
What your overhead will be will depend a lot on your space/setup. These guys have a pretty good one: http://www.youtube.com/watch?v=G5f_e4P6gMA
What your overhead will be will depend a lot on your space/setup. These guys have a pretty good one: http://www.youtube.com/watch?v=G5f_e4P6gMA
Their ventilation works because the rigs are in a very large warehouse. A ventilation system like that would also need to have an intake in my space, as I have 800 sqft. Another thing to consider is that I am in FL which means if you are pulling a lot of air in, the humidity would fluctuate in the ventilated space quite a bit.
February 19, 2012, 01:48:35 PM
yeah, sorry.. these should be about 12.5-13.5 amps each, 120v @ 1500-1600w. I think we were getting around 2.4 ghs per machine @ ~1600w.
What your overhead will be will depend a lot on your space/setup. These guys have a pretty good one: http://www.youtube.com/watch?v=G5f_e4P6gMA
What your overhead will be will depend a lot on your space/setup. These guys have a pretty good one: http://www.youtube.com/watch?v=G5f_e4P6gMA
February 19, 2012, 01:32:46 PM
Wow. $100k for 60Gh. 
I could potentially host this equipment for you, but it would require a significant upgrade of either the HVAC or a new ventilation system. There would also be expenses for racks, wiring, electricial and probably another dedicated room for rigs.
I am assuming that your quote of 16 amps per rig is including the 20% overhead as my calculations show these rigs should be pulling about 12 amps at 120 volts.
My facilities include a three phase 200 amp service so at 208v each rig should pull about 7 amps. Looks like I could run 4 rigs per 40 amp circuit with this configuration leaving plenty of spare room on each circuit.
PM if you are interested. There would be a lot of details to work out but it is doable.
EDIT:
My base power rate is $0.07585/Kw for the 208v.
I could potentially host this equipment for you, but it would require a significant upgrade of either the HVAC or a new ventilation system. There would also be expenses for racks, wiring, electricial and probably another dedicated room for rigs.
I am assuming that your quote of 16 amps per rig is including the 20% overhead as my calculations show these rigs should be pulling about 12 amps at 120 volts.
My facilities include a three phase 200 amp service so at 208v each rig should pull about 7 amps. Looks like I could run 4 rigs per 40 amp circuit with this configuration leaving plenty of spare room on each circuit.
PM if you are interested. There would be a lot of details to work out but it is doable.
EDIT:
My base power rate is $0.07585/Kw for the 208v.
February 19, 2012, 01:16:56 PM
You are going to need about 400 amps to handle these 25 machines @ ~16 amps each.
Jump to: