Efficiency of 7970(youre gonna like this)

[ailikun]

So ive decided to check if 7970 will go below the core volt: of 0.925.. and it does..

i was able to mine stable at 0.850 volt -850Mhz/280 getting something about 490-500Mhs...

and here's my power consuption from the wall

220 watts for the whole system 2x7970(asic quility about 80)
so subtract 70 watts that my system consumes

that makes 150 watt for both cards

75 watt each card

so it makes 6.66 mhash per watt))

sweeet)

[1713953468]

1713953468

[1713953468]

1713953468

[1713953468]

1713953468

[tosku]

6.66 Mhashes per joule, or (6.66 Mhashes per second) per watt.

1 watt for 1 second = 1 joule.

[AzN1337c0d3r]

i was able to mine stable at 0.850 volt -850Mhz/280 getting something about 490-500Mhs...

I'm going to assume that's really supposed to say 450 MHz.

460 MHz, yields me 275 MH/s, so 450 should be in the ballpark of 270. You aren't mining with the most efficient settings.

so subtract 70 watts that my system consumes

How did you measure your system idle consumption?

[ailikun]

no what im saying is i mined at core clock 850 mhz, 300 mhz memory clock
my voltage is 0.850 and im getting 500 mh/s , whats so difficult to understand?

[AzN1337c0d3r]

no what im saying is i mined at core clock 850 mhz, 300 mhz memory clock
my voltage is 0.850 and im getting 500 mh/s , whats so difficult to understand?

Because your math is almost incomprehensible, but I think I finally figured out the madness.

You also didnt answer my 2nd question about how you measured your system idle power though.

[ailikun]

i powered my computer without any gpus
and measured its idle power consuption

[ailikun]

ill let it run for a few hours, and then post it...

theres no madness... you just have to believe it))

[Dexter770221]

Sweet indeed. What cards are those?

[AzN1337c0d3r]

Theres no madness... you just have to believe it))

Oh I believe it, I get 10 MH/J myself. That's not the issue. Your original post was formatted in a crazy manner. You started off with 1 card numbers, then did calculations for a whole system, and then went back to a single card.

Here's how I would have made it look like:

So ive decided to check if 7970 will go below the core volt: of 0.925.. and it does..

ASIC Quality: 80%
Voltage: 0.85V
Core: 850 MHz
Mem: 250 MHz

2x7970: 1100 MH/s

My power consumption at the wall is 220W.

I measured the idle power without any cards plugged in at 70W.

1100 MH/s / (220 - 70) watts = 6.67 MH/J

sweeet)

[zvs]

why would you run a 7970 with such settings? 

[bulanula]

why would you run a 7970 with such settings? 

Because not every has their mommy and daddy paying for their power usage

[crazyates]

why would you run a 7970 with such settings? 

a 10% drop in hash speed for a 25% drop in power makes it much more profitable for those of us paying for more than ~13c/KWh. Also, less V means less heat, which means lower fan speeds, which means your fans last longer. There is a place for heavy overclocking, and there is a place for heavy undervolting.

[AzN1337c0d3r]

lower fan speeds, which means your fans last longer.

Citation needed.

[Gabi]

lower fan speeds, which means your fans last longer.

Citation needed.

It's a known fact that running these fans at lower speed is better.
Running a normal GPU fan at 100% will ruin it

[AzN1337c0d3r]

lower fan speeds, which means your fans last longer.

Citation needed.

It's a known fact that running these fans at lower speed is better.

If this is a fact, there would be proof/evidence of it. Please cite.

AFAIK, bearing life is related to temperature and running a fan higher tends to lower temperatures when you're trying to cool a 150-200W device.

[crazyates]

lower fan speeds, which means your fans last longer.

Citation needed.

It's a known fact that running these fans at lower speed is better.

If this is a fact, there would be proof/evidence of it. Please cite.

AFAIK, bearing life is related to temperature and running a fan higher tends to lower temperatures when you're trying to cool a 150-200W device.

OK, so longer fan life is a result of keeping the bearing temperatures down. Again, undervolting can accomplish this.

[bulanula]

lower fan speeds, which means your fans last longer.

Citation needed.

It's a known fact that running these fans at lower speed is better.

If this is a fact, there would be proof/evidence of it. Please cite.

AFAIK, bearing life is related to temperature and running a fan higher tends to lower temperatures when you're trying to cool a 150-200W device.

Exactly. Running fans at 100% is actually beneficial in the long run and much better than 80% say.

Find it very funny that most of the miners say otherwise so that other miners have their fans failing and less difficulty for the misinforming miners

[AzN1337c0d3r]

OK, so longer fan life is a result of keeping the bearing temperatures down. Again, undervolting can accomplish this.

Yes, but the question posed was that does increasing fan speed actually decrease fan life? No one was asking "Does undervolting increase fan life?"

[conspirosphere.tk]

75 watt each card

That sounds almost competitive with BFLs single, price/performance speaking.
Nice.

[phelix]

So ive decided to check if 7970 will go below the core volt: of 0.925.. and it does..

i was able to mine stable at 0.850 volt -850Mhz/280 getting something about 490-500Mhs...

and here's my power consuption from the wall

220 watts for the whole system 2x7970(asic quility about 80)
so subtract 70 watts that my system consumes

that makes 150 watt for both cards

75 watt each card

so it makes 6.66 mhash per watt))

sweeet)

how did you set the voltage?

what are the default voltages for level0 and level1 ?