5x7950 Gigabyte WF3 Rig using 1475 Watts!!!

[thedonvon]

I am running 5 7950s, Gigabyte WF3 with the f43 undervolted bios and the rig is using 1475 watts at the wall.  I just purchased a kill-a-watt meter and am in disbelief.  I have flashed the f43 bios to the cards, so the voltage of the cards is now 1.09 volts.  That is like 300W per card!!!!!  This seems way to high.  I have read these cards are supposed to be using less than 200W per card.  Any suggestions?

[zackclark70]

card seting 1050core  1250 ram   1.050v   630kh per card  3 cards 705w  4 card 920w

reaper setings

protocol litecoin

worksize 256

aggression 20
threads_per_gpu 1
sharethreads 18
lookup_gap 2
gpu_thread_concurrency 20992

[Flashman]

Now calculate for 80% PSU efficiency and knock off about 200W for the motherboard, CPU, drives etc..... .... ...

[zackclark70]

Now calculate for 80% PSU efficiency and knock off about 200W for the motherboard, CPU, drives etc..... .... ...

was that to me ? if so thats what i pull from the wall

[thedonvon]

i have a 43 wat cpu, laptop hdd, and my PSU is an 80plus gold efficient PSU...so i understand i need to knock off some for mobo and psu inefficiency but it should not be that drastic

card seting 1050core  1250 ram   1.050v   630kh per card  3 cards 705w  4 card 920w

reaper setings

protocol litecoin

worksize 256

aggression 20
threads_per_gpu 1
sharethreads 18
lookup_gap 2
gpu_thread_concurrency 20992

Are you using the same card?  Gigabyte WF3 with f43 bios?

[zackclark70]

i am using saphire vapor x cards but the setings should work the neer the same

[computerparts]

Now calculate for 80% PSU efficiency and knock off about 200W for the motherboard, CPU, drives etc..... .... ...

+1 depending on what psu and cpu he is running could be less.

[thedonvon]

Now calculate for 80% PSU efficiency and knock off about 200W for the motherboard, CPU, drives etc..... .... ...

+1 depending on what psu and cpu he is running could be less.

I am running a 55w CPU and my power supply is 80 plus gold efficient.

[Bakaboy]

I get roughly the same when running a z77a-GD55 + G1610 + 5x7950 Gigabyte WF3 (1100/1400mem). Most of the time however, I'm probably around  ~50-90 watts lower (that you stated)  probably attributed to:

1. I run dual gold PSU's so the efficiency is close to peak rated.
2. I run them cool < 70C so with fan RPMS ~1800-2000RPM. This might improve longevity, but since I have to use dual box fans forcing air through the rig, that costs another 100W combined.

Try to compute if the additional power is worth it (if it matters that is). I live in an area where power is relatively cheap, however, the power bill is still substantial. 

[thedonvon]

I get roughly the same when running a z77a-GD55 + G1610 + 5x7950 Gigabyte WF3 (1100/1400mem). Most of the time however, I'm probably around  ~50-90 watts lower (that you stated)  probably attributed to:

1. I run dual gold PSU's so the efficiency is close to peak rated.
2. I run them cool < 70C so with fan RPMS ~1800-2000RPM. This might improve longevity, but since I have to use dual box fans forcing air through the rig, that costs another 100W combined.

Try to compute if the additional power is worth it (if it matters that is). I live in an area where power is relatively cheap, however, the power bill is still substantial. 

That is almost my rig exactly.  I am running a z77a-gd65 and 5 WF3 (1100/1400)  I have one box fan blowing air over the cards.  They run at around 70c.  I am using a gold rated 1300w PSU.  I think our numbers should be much much lower.  I unplugged one card and am getting a reading of 1170 which means that 1 card is using almost 300w.  Thats crazy.

[BlazinBeaches]

That sounds about right dude

200+ per card, plus the mobo/cpu/ram

+ 10%+/- loss in PSU efficiency.

Plus monitor, router, cable modem, printer, keyboard, mouse, fans, beer cooler , etc and whatever else may or may not be plugged in

[grobbes]

I run 4 at less than 1000 watts so not sure why people are saying this is normal.

[Bakaboy]

I run 4 at less than 1000 watts so not sure why people are saying this is normal.

Just curious, at what voltage, core and memory clock? Thanks.

[dimke_yu]

On my rig with 4 x 7950 Vapor-x when mining scrypt power consumption from wall is around 980W. Cards are on stock voltage in range from 1.06 to 1.12. They run stable at 630 KH/s.

[ssateneth]

gigabyte triple fan cards are voltage locked, period. no amount of bios flashes or editing will change that. unless you have the multimeter or kill-a-watt pictures to prove me wrong, this is what you will need to deal with when messing with voltage locked gpus and overclocking with scrypt.

I run 6 x 7970 on each computer, powered by only a 1300w psu. They are all pure reference and I can change the volts to whatever I want. They hum along like any other day, no problems

[HellDiverUK]

Mining Litecoins (or any other scrypt) uses WAY more power than SHA256.  My machine uses 200W more at the wall when doing LTC compared to BTC.  So, some people may be comparing apples to oranges here.

[zackclark70]

Mining Litecoins (or any other scrypt) uses WAY more power than SHA256.  My machine uses 200W more at the wall when doing LTC compared to BTC.  So, some people may be comparing apples to oranges here.

i have 4 7950s scrypt 2,500kh+ 913w frowm the wall including monator

[ma_rine_sa]

7950 do have good hash to watt ratio... but you got to lower your hash rate.

best i could do is 5 * 580khash for just over 1000watts

soon as i go over 600 khash it can EASILY go over 250watts each card.

your power consumption is about right but if you really want to save on power you have to shave off the hash rates.

if only btc diff was lower because i was doing 5 * 550 mhash for 840 watts!!!

sucks to pay 27c/kw

[Bakaboy]

gigabyte triple fan cards are voltage locked, period. no amount of bios flashes or editing will change that.

Not exactly. For Gigabyte 7950 WF3s (AFAIK):

1. The original rev 1.0 boards are not voltage locked.
2. The official bios from gigabyte F43 (1.09V/900Mhz), FY1 (1.25V?/1000Mhz), FX1(1.25V?/1000Mhz) have locked voltages for the Rev 2.0 boards. However, if you use robnitro's hacked FY1 bios, this will allow you to change the voltage using cgminer or Trixx. I tested this bios and the voltage control works well, however I still run at 1.09 as going below makes the cards unstable @1100Mhz.
3. The FT0 bios was also hacked by robnitro and according to users, the voltage control works as well.

Regardless of the voltage unlock capabilities however, the undervoltage/overclocking capability of each specific GPU is closely tied to the ASIC quality. If you have a card with a very low ASIC quality, chances are you'll have to bump the voltage or even underclock it; depending on what you are aiming for, YMMV.

[BlazinBeaches]

gigabyte triple fan cards are voltage locked, period. no amount of bios flashes or editing will change that. unless you have the multimeter or kill-a-watt pictures to prove me wrong, this is what you will need to deal with when messing with voltage locked gpus and overclocking with scrypt.

I run 6 x 7970 on each computer, powered by only a 1300w psu. They are all pure reference and I can change the volts to whatever I want. They hum along like any other day, no problems

What PSU?  6x 7970s on 1300 watts?  What voltage do you run?  That's really good

My 6x7970s with mobo,cpu,ram,etc pull 1650 from the wall.  But I also have a bunch of fans hooked up, so it's probably more like 1550.  That's at 1.1 vddc.  There are 2 PSUs though, one is a 1200 Gold the other is a just a 520 watt 80+.  I'm guessing the little psu isn't helping.

**ahh I also have a 3770k on there though, forgot about that.  will be dropping in a g1610 this weekend.  Got a few of 'em sitting in my closet, just waiting for me to build dedicated racks  

here you go bro if you guys want to jump on some while they are only $42.99
http://www.amazon.com/Intel-Celeron-2-60GHz-Processor-BX80637G1610/dp/B00B4BJYVU