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Other => Beginners & Help => Topic started by: kano on July 27, 2011, 03:07:13 AM



Title: Real power Watt usage (6950)
Post by: kano on July 27, 2011, 03:07:13 AM
Wanted to discuss this in the hardware related threads that already exist, but since I just joined ...

So I've been running a 6950 for a bit over a day and thought I really should check up on these stats we all see about power ...
Coz that eats up a sizeable part of the possible return for mining

(I'm in Aus)
Local Jaycar store has one of the cheap power meters for $20 so I got one and plugged it in front of the rig ...

I have no display card other than the 6950 so there is already some power just running: around 90 W
That might seem low to some? or is it high?
But I've no HDD, and use a i3-540 32nm only 2GB system RAM running xubuntu

Start mining and bang - it jumps up to 380 W - single 6950 card (Gigabyte HD 6950 1GB RAM)
(aside: xubuntu drops the CPU to 1.2GHz and still only uses 15% CPU when mining ~340Mh/s)

I've ordered a 2nd 6950 to arrive today

Anyone else actually checked their real Watt usage with a meter and got some useful comparison info?

Here is Aus kWh is quite expensive (from reading around it may be more than 2x USA)


Title: Re: Real power Watt usage (6950)
Post by: what@3 on July 27, 2011, 03:22:18 AM
You'll notice a pretty big decrease in power consumption if you get the mem clocks lower. I think mine came in at ~200-225W.


Title: Re: Real power Watt usage (6950)
Post by: tysat on July 27, 2011, 03:25:59 AM
At 380W usage for mining, I calculate 9.12 kWh per day.  And at 340 mh/s it's about 0.20 BTC per day currently.  Should be profitable.


Title: Re: Real power Watt usage (6950)
Post by: kano on July 27, 2011, 03:53:57 AM
At 380W usage for mining, I calculate 9.12 kWh per day.  And at 340 mh/s it's about 0.20 BTC per day currently.  Should be profitable.
Yes certainly profitable at the moment ... but wow it seems marginal.
(Edit: my electricity is $0.291 kWh ...)

@what@3
yeah thanks for the reminder :)
I keep forgetting to play with the OC/(UC)
Its the middle of winter here in Aus so I'm going to keep this in the underground garage where I live
(garage is ready with a tested and working NetGear XAVB1004)
So once it's down there wher it is a lot colder than inside I will OC the GPU's but I keep forgetting I can UC the RAM asap - and that much drop would be amazing ... gotta do that today!


Title: Re: Real power Watt usage (6950)
Post by: what@3 on July 27, 2011, 04:05:00 AM
you're killing me with all this talk of coldness...... its been a stifling 100F+ for weeks now


Title: Re: Real power Watt usage (6950)
Post by: SMOKEU on July 27, 2011, 05:37:13 AM
Is your 6950 flashed to a 6970? My whole computer running a flashed 6970 925MHz (stock memory clocks) @ 1.2V with an i7 2600K running at stock clocks uses around 320W while mining according to my power meter. This excludes the monitor as the monitor goes on standby mode. I'm getting a touch over 400Mhash/s.


Title: Re: Real power Watt usage (6950)
Post by: what@3 on July 27, 2011, 05:52:26 AM
what flash method did you use and 6950 brand please??




Title: Re: Real power Watt usage (6950)
Post by: kano on July 27, 2011, 06:13:33 AM
Is your 6950 flashed to a 6970? My whole computer running a flashed 6970 925MHz (stock memory clocks) @ 1.2V with an i7 2600K running at stock clocks uses around 320W while mining according to my power meter. This excludes the monitor as the monitor goes on standby mode. I'm getting a touch over 400Mhash/s.
It's a stock Gigabyte 6950
(I was just about to walk out the door to go get the 2nd one - will as soon as I post this)

Yeah I heard that the 6950 is a 6970 with shaders disabled ... what's involved in changing that (and risks?)

amdoverdrivectrl doesn't let me set the Mem MHz below 745 (default GPU=870)  :(

Though at least that does save 30W !!!! (now 350W)