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firefop
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December 14, 2012, 04:51:20 AM |
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I for example run some fpgas, and a bunch of 5770 (most power friendly mining card there is if you configure it correctly).
Hum, no. A 7970 beats the 5770 any day in terms of Mhash/Joule. It does 3.1 out of the box. 4+ when undervolted/underclocked. If you think your 5770 beats that, you must be incorrectly measuring its power consumption (eg. you measure at the wall and only measure the difference between idle and load, and incorrectly assume the card draws 0W at idle). It's possible I screwed the the math. I'm showing a difference of 42 watts between idle and loaded - with a single 5770. The cards limited to 75w (per ATI). A 7970 is ~200 watts difference between idle and load. (and limited to 250 per ATI). Are you getting 600 mh/s out a 7970? If not then my 5770s are out preforming you and using less power. |
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According to NIST and ECRYPT II, the cryptographic algorithms used in
Bitcoin are expected to be strong until at least 2030. (After that, it
will not be too difficult to transition to different algorithms.)
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mrb
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December 14, 2012, 05:51:51 AM
Last edit: December 14, 2012, 06:04:54 AM by mrb |
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I for example run some fpgas, and a bunch of 5770 (most power friendly mining card there is if you configure it correctly).
Hum, no. A 7970 beats the 5770 any day in terms of Mhash/Joule. It does 3.1 out of the box. 4+ when undervolted/underclocked. If you think your 5770 beats that, you must be incorrectly measuring its power consumption (eg. you measure at the wall and only measure the difference between idle and load, and incorrectly assume the card draws 0W at idle). It's possible I screwed the the math. I'm showing a difference of 42 watts between idle and loaded - with a single 5770. The cards limited to 75w (per ATI). A 7970 is ~200 watts difference between idle and load. (and limited to 250 per ATI). Are you getting 600 mh/s out a 7970? If not then my 5770s are out preforming you and using less power. Yes, me and many people get 650-700 Mhash/s per 7970. 7970 is 32nm. 5770 is 40nm. The 32nm chip is naturally more power efficient. Also you made the exact mistake I predicted: incorrectly assuming the 5770 draws 0W at idle therefore you think mining only takes 42W. The 5770 actually draws 18W at idle per its specs. That means your card as a whole is closer to ~60W when mining. Taking into account this 18W baseline load is important when comparing different cards. Or else, imagine if a card was so inefficient that it would draw 100W when idle and 105W when under load. People would be claiming that mining only takes 5W, therefore making it the most efficient card of all! |
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firefop
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December 14, 2012, 10:02:41 PM
Last edit: December 14, 2012, 10:35:04 PM by firefop |
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Yes, me and many people get 650-700 Mhash/s per 7970.
7970 is 32nm. 5770 is 40nm. The 32nm chip is naturally more power efficient.
Also you made the exact mistake I predicted: incorrectly assuming the 5770 draws 0W at idle therefore you think mining only takes 42W. The 5770 actually draws 18W at idle per its specs. That means your card as a whole is closer to ~60W when mining.
Taking into account this 18W baseline load is important when comparing different cards. Or else, imagine if a card was so inefficient that it would draw 100W when idle and 105W when under load. People would be claiming that mining only takes 5W, therefore making it the most efficient card of all!
Argue it anyway you like - you're still incorrect. Measuring at the wall with 3x 5770 and then measuring the same machine with a 7970 instead... will clearly show which is ahead. per specs maximum draw for a 5570 is 108W. Lets use that number. My cards (which are drawing ~75 are getting over 200mh/s). 5770 - 108w @ 200 mh/s. 7970 - ~300w @ (lets say) 600 mh/s. Now based on 'worst case' numbes the 7970 is slightly ahead. The difference between the idle draw on the 5770 and the 7970 is 3 watts. Also idle doesn't matter, since you can't mine while idle. It's fine, rest assured that your 7970 will probably resell for a few hundred bucks once asics hit... while I'm losing slightly more money if I can't resell mine. Due to them only costing 1/6th of the price. |
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mrb
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December 15, 2012, 01:10:14 AM
Last edit: December 15, 2012, 02:22:34 AM by mrb |
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Yes, me and many people get 650-700 Mhash/s per 7970.
7970 is 32nm. 5770 is 40nm. The 32nm chip is naturally more power efficient.
Also you made the exact mistake I predicted: incorrectly assuming the 5770 draws 0W at idle therefore you think mining only takes 42W. The 5770 actually draws 18W at idle per its specs. That means your card as a whole is closer to ~60W when mining.
Taking into account this 18W baseline load is important when comparing different cards. Or else, imagine if a card was so inefficient that it would draw 100W when idle and 105W when under load. People would be claiming that mining only takes 5W, therefore making it the most efficient card of all!
Argue it anyway you like - you're still incorrect. Measuring at the wall with 3x 5770 and then measuring the same machine with a 7970 instead... will clearly show which is ahead. per specs maximum draw for a 5570 is 108W. Lets use that number. My cards (which are drawing ~75 are getting over 200mh/s). 5770 - 108w @ 200 mh/s. 7970 - ~300w @ (lets say) 600 mh/s. These numbers show I was correct! - the 7970 is more power efficient (in fact a lot more because your numbers are out of whack... at 600 Mhash/s the 7970 draws ~200W -- I measured mine at 193W with a clamp meter). Not sure why you say I was "incorrect"  The difference between the idle draw on the 5770 and the 7970 is 3 watts.
Yes but when you ignore the 18W at idle for the 5770, you ignore 17% of its total power draw, and when you ignore the 15W at idle for the 7970, you ignore 6% of its total power draw. See the difference? 6% vs 17%? This is the significance I am talking about. |
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Soros Shorts
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December 15, 2012, 02:00:20 AM |
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7970 - ~300w @ (lets say) 600 mh/s.
Huh? I have a single 7970 "space heater" running at 620MHs and drawing 275W at the wall for the entire system. Admittedly the other components are efficient (Sandy Bridge i5, SSD, 80 Plus platinum PS), but still ... |
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mrb
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December 15, 2012, 02:23:18 AM |
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7970 - ~300w @ (lets say) 600 mh/s.
Huh? I have a single 7970 "space heater" running at 620MHs and drawing 275W at the wall for the entire system. Admittedly the other components are efficient (Sandy Bridge i5, SSD, 80 Plus platinum PS), but still ... Welcome to the world of people tweaking numbers in order to save face in an online argument... |
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firefop
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December 15, 2012, 05:20:15 AM |
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7970 - ~300w @ (lets say) 600 mh/s.
Huh? I have a single 7970 "space heater" running at 620MHs and drawing 275W at the wall for the entire system. Admittedly the other components are efficient (Sandy Bridge i5, SSD, 80 Plus platinum PS), but still ... Welcome to the world of people tweaking numbers in order to save face in an online argument... No. We used maximum draw per ATI for both cards. Stock no tweaking the 7970 pulls down ~560. |
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mrb
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December 15, 2012, 05:40:03 AM |
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7970 - ~300w @ (lets say) 600 mh/s.
Huh? I have a single 7970 "space heater" running at 620MHs and drawing 275W at the wall for the entire system. Admittedly the other components are efficient (Sandy Bridge i5, SSD, 80 Plus platinum PS), but still ... Welcome to the world of people tweaking numbers in order to save face in an online argument... No. We used maximum draw per ATI for both cards. Stock no tweaking the 7970 pulls down ~560. You are still wrong. Because the official TDP of the 7970 is 250W. So even when looking at stock numbers, the 7970 is more efficient by ~21%: - 7970: 560 Mhash/s at 250W = 2.24 Mhash/Joule - 5770: 200 Mhash/s at 108W = 1.85 Mhash/Joule If you move the argument to undervolted/fine-tuned settings, or to actual measured power, then the 7970 increases or keeps its lead because, as I pointed out, it doesn't even use close to 250W when mining (only ~200W). |
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Unacceptable
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December 15, 2012, 08:40:39 AM |
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My system: 1000 watt Kingwin PSU AMD 965BE,3.4ghz,no OC 8 gig DDR3 1600 (PC3 12800) 3-320gig HDD's 5-80mm fans(lighted) Visiontek 7970 While mining the whole system uses 380 watts,while idle 150 watts.I'm assuming my 7970 uses 230 watts max (1050mhz gpu clock,1265mhz memory clock=620mhs). Still beats my 6970 xfire setup,680 watts for 820mhs.Glad I upgraded  |
"If you run into an asshole in the morning, you ran into an asshole. If you run into assholes all day long, you are the asshole." -Raylan Givens Got GOXXED ?? https://www.youtube.com/watch?v=9KiqRpPiJAU&feature=youtu.be"An ASIC being late is perfectly normal, predictable, and legal..."Hashfast & BFL slogan  |
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joshv06
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December 15, 2012, 09:19:42 AM |
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My quad 7970 water cooled system uses 1KWhr at 2.6ghs, stock voltage, 1160 core, 170 mem.
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mrb
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December 15, 2012, 11:52:14 PM |
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My quad 7970 water cooled system uses 1KWhr at 2.6ghs, stock voltage, 1160 core, 170 mem.
That is 2.6 Mhash/Joule. Better than the 5770, as expected. |
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joshv06
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December 16, 2012, 03:04:22 PM |
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My quad 7970 water cooled system uses 1KWhr at 2.6ghs, stock voltage, 1160 core, 170 mem.
That is 2.6 Mhash/Joule. Better than the 5770, as expected. Yeah, just that one of the cards is lazy and has kept me lowering the core clock. I used to mine at 1175 mem with stock voltage, but it seems that it kept crashing and had to lower 5 mhz every 2 months or so. It is my second card, and blinks a red light on the PCB, what does this mean? |
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peasant
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December 16, 2012, 06:01:15 PM
Last edit: December 16, 2012, 06:11:51 PM by peasant |
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When i had my 7970 system mining it was producing 650Mh/s and only pulling 380watts at the wall. That included a gaming system setup (quad-core amd cpu, 6gb ram, optical drive, traditional HD, and a couple of heavy duty 120mm case fans). That number also counted my wireless router, cable modem, plugged in monitor but turned off and power strip. There is no way that card is pulling more than 250watts, and i'm sure it's closer to 220-230 at full load with simple low risk setting like 65% fan 1100gpu/950ram at 67degrees. I'm glad i made the right choice. That card will serve me for years to come if i keep it.
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