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SeanArce (OP)
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June 19, 2013, 11:04:02 PM |
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What's more promising?
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SeanArce (OP)
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June 20, 2013, 02:36:10 AM |
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I want to feel apart of the bitcoin community. Which is a better option?
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Gomeler
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June 20, 2013, 04:34:32 AM |
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2x HD 7950s for litecoin. Mining BTC on GPUs isn't wise.
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neo101one
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June 20, 2013, 04:42:22 AM |
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you might save money getting 4 7850s, but might need a bigger psu. the 2 7970s could run on a 750w psu.
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SeanArce (OP)
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June 20, 2013, 05:54:17 PM |
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2x HD 7950s for litecoin. Mining BTC on GPUs isn't wise.
I'm going to be mining alternative crypto |
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SeanArce (OP)
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June 20, 2013, 05:55:30 PM |
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you might save money getting 4 7850s, but might need a bigger psu. the 2 7970s could run on a 750w psu.
How many watt psu for 4 7850's? |
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BlazinBeaches
Member
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Activity: 98
Merit: 10
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June 20, 2013, 05:59:09 PM |
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7850s draw about 130watt each
7950s are 200
7970s are 250
+/-
plus mobo/cpu/ram
plus 15% breathing room
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zackclark70
Legendary
Offline
Activity: 868
Merit: 1000
ADT developer
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June 20, 2013, 06:02:16 PM |
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you can get 3 7950s for the price of 2 7970s and only need a good 750w psu ( i have a 3 card rig with 1950kh 720w from the wall )
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zvs
Legendary
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Activity: 1680
Merit: 1000
https://web.archive.org/web/*/nogleg.com
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June 20, 2013, 06:53:31 PM |
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7790's are about 15% slower than 7850's for bitcoins (duno about scrypt currencies).. they only use about 70-75 watts
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TheSpiral
Full Member
Offline
Activity: 322
Merit: 113
Sinbad Mixer: Mix Your BTC Quickly
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June 21, 2013, 09:26:51 AM |
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7790's are about 15% slower than 7850's for bitcoins (duno about scrypt currencies).. they only use about 70-75 watts
They're very close for SHA, 7790's are much worse for scrypt. |
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zackclark70
Legendary
Offline
Activity: 868
Merit: 1000
ADT developer
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June 21, 2013, 09:33:51 AM |
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if you are mining any scrypt coin stick with 7950s if you can as thay have a higher resale value ( do not buy xfx )
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rovchris
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June 21, 2013, 11:45:48 AM |
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Just out of interest why are 7850's better than 7970's
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SeanArce (OP)
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June 22, 2013, 03:51:27 PM |
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Just out of interest why are 7850's better than 7970's
I'm guessing its more cost effective and the initial price of the 7850 is a lot better |
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The Extreme
Newbie
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Activity: 34
Merit: 0
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June 25, 2013, 06:08:36 AM |
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No contest...
4x 7850:
Max Power Draw = 4*130W = 520 W
Approx LTC Hashrate = 4*330 kH/s = 1.32 MH/s
Kilohashes/Watt: 2.54
Upfront Cost = 4*$190 = $760
2x 7950:
Max Power Draw = 2*180W = 360 W
Approx LTC Hashrate = 2*620 kH/s = 1.24 MH/s
Kilohashes/Watt: 3.44
Upfront Cost = 2*$300 = $600
2x 7970:
Max Power Draw = 2*270W = 540 W
Approx LTC Hashrate = 2*725 kH/s = 1.5 MH/s
Kilohashes/Watt: 2.78
Upfront Cost = 2*$420 = $840
The 7950s are typically all but impossible to beat as a mining card for any non-BTC mining.
In this example, the two 7950s have the cheapest upfront cost, consume the least power, and trounce the other options in terms of hashes per watt.
It's my understanding that for mining, the Pitcairn-based boards are not the best option; for a mining rig, consider only Tahiti-based cards (7870XT or higher).
That said, the 7950 is almost always the best bet, regardless of the number of cards. Hope this helps...
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rovchris
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June 25, 2013, 06:22:42 AM |
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No contest...
4x 7850:
Max Power Draw = 4*130W = 520 W
Approx LTC Hashrate = 4*330 kH/s = 1.32 MH/s
Kilohashes/Watt: 2.54
Upfront Cost = 4*$190 = $760
2x 7950:
Max Power Draw = 2*180W = 360 W
Approx LTC Hashrate = 2*620 kH/s = 1.24 MH/s
Kilohashes/Watt: 3.44
Upfront Cost = 2*$300 = $600
2x 7970:
Max Power Draw = 2*270W = 540 W
Approx LTC Hashrate = 2*725 kH/s = 1.5 MH/s
Kilohashes/Watt: 2.78
Upfront Cost = 2*$420 = $840
The 7950s are typically all but impossible to beat as a mining card for any non-BTC mining.
In this example, the two 7950s have the cheapest upfront cost, consume the least power, and trounce the other options in terms of hashes per watt.
It's my understanding that for mining, the Pitcairn-based boards are not the best option; for a mining rig, consider only Tahiti-based cards (7870XT or higher).
That said, the 7950 is almost always the best bet, regardless of the number of cards. Hope this helps...
What about the fact that you would require additional motherboards, CPU's, PSU's to run more cards for the same Hash rate. Realistically you can only connect 4 cards to one motherboard and expect any kind of stability. When you factor in these additional costs and the power overhead of the additional hardware - I am not sure that the 7950's are better. |
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The Extreme
Newbie
Offline
Activity: 34
Merit: 0
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June 25, 2013, 06:29:09 AM |
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No contest...
4x 7850:
Max Power Draw = 4*130W = 520 W
Approx LTC Hashrate = 4*330 kH/s = 1.32 MH/s
Kilohashes/Watt: 2.54
Upfront Cost = 4*$190 = $760
2x 7950:
Max Power Draw = 2*180W = 360 W
Approx LTC Hashrate = 2*620 kH/s = 1.24 MH/s
Kilohashes/Watt: 3.44
Upfront Cost = 2*$300 = $600
2x 7970:
Max Power Draw = 2*270W = 540 W
Approx LTC Hashrate = 2*725 kH/s = 1.5 MH/s
Kilohashes/Watt: 2.78
Upfront Cost = 2*$420 = $840
The 7950s are typically all but impossible to beat as a mining card for any non-BTC mining.
In this example, the two 7950s have the cheapest upfront cost, consume the least power, and trounce the other options in terms of hashes per watt.
It's my understanding that for mining, the Pitcairn-based boards are not the best option; for a mining rig, consider only Tahiti-based cards (7870XT or higher).
That said, the 7950 is almost always the best bet, regardless of the number of cards. Hope this helps...
What about the fact that you would require additional motherboards, CPU's, PSU's to run more cards for the same Hash rate. Realistically you can only connect 4 cards to one motherboard and expect any kind of stability. When you factor in these additional costs and the power overhead of the additional hardware - I am not sure that the 7950's are better. Hmmm... rovchris, I'm not sure I follow. I agree with your assessment that 4 GPUs is the realistic maximum on any one mobo. But with the 7950's (or 7970's, for that matter) he would only need two cards instead of four. One more advantage to the 79xx cards... |
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rovchris
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June 25, 2013, 06:46:45 AM |
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Sorry man I was not very clear.
I was just saying in the situation where lets say you wanted to build a 10mhs rig (scrypt) - you would require more cards if you using the 7950's and hence more of all the supporting hardware.
In this situation though as the OP only wanted to build a rig of a set size you make a very good case.
I was just picking the experts brains here!
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chadtn
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June 28, 2013, 10:59:55 AM |
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I was able to get away with running two 7970's on a 660 watt power supply for a couple of weeks with no problem. I decided to upgrade before I started over clocking the cards though.
Chad
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Equate
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June 28, 2013, 12:57:07 PM |
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2 7950 better than 2 7970 if you want to mine LTC
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Eastwind
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June 28, 2013, 02:16:01 PM |
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you can get 3 7950s for the price of 2 7970s and only need a good 750w psu ( i have a 3 card rig with 1950kh 720w from the wall )
I think it is better option. 7950 works better than 7850 on LTC, as the memory bandwidth of 7950 is 384 bit instead of 256 bit. memory bandwidth matters on LTC mining. |
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