Quote from: drakoin on January 20, 2014, 09:00:38 PM

Quote from: Quacko on January 19, 2014, 04:52:22 PM

Hey guys. I have a Gigabyte 280x OC and had to lower the voltages otherwise it would crash my pc even on stock speeds. I currently run it @ 1050/1500 @ 1.025V but tbh I don't see a difference in powerdraw between 1.094V and my current 1.025V, I might even be able to get it lower that 1.025, haven't tried yet. I get about 729kh/s. Am sure I can change the voltages because before I changed it, it instantly shuts down my pc. And when I looked at the voltage meter when it was on stock voltage (1.256V crazy huh?) it gets up to 500W! Any ideas why both voltage settings draw about the same from the wall?

My only idea now is ... to measure longer. Watts can be fluctuating about 15-20 W, so I always watch the Wattmeter for a minute or two, and then guess an average. If you do that, you might notice that there actually is a small difference in Watts between 1.094V and 1.025V?

1.256V stock voltage sounds to me, as if the card was perhaps intended to be overclocked?

729kh/s is impressively high. If you don't pay for electricity, that is.
Please measure the Watts in two situations: at 729kh/s, and at "OFF" when you (g)pu (d)isable the cards in cgminer. Please report back both values.

And then try out, if you can find a khash/Watt optimizing sweet spot like the (C) that I describe in posting #28. Please come back to us with details if you can find such a sweet spot for your card.

k, thx I'll check on of these days when I have the time again.
729 isn't very high though, my other 280x cards go @ 773kHs on stock voltages. I havent tried lowering the voltages yet, I probably can a bit.
Here is my question though: As long as I make near 3x as much money with my mining than what I am spending on electricity, I have to lower power consumption at least 30% for every 10% of hashing power I lose for underclocking and undervolting. Right? That sounds hard to do, that would mean that my powerconsumption needs to come down more than 100W, I find that hard to believe that it will...