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The Efficiency Thread.

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What a kill-a-watt shows is what you are paying for...

It could help to figure out actual power draw is, but you are paying for what's coming out of the wall anyway.
 
UPDATE:

Silver_Pharaoh|270x+6850|760Kh|400w|1.9Kh/w

Undervolting saved 40 watts, and overclocking a bit more gave an extra 10 Kh :thup:
 
I just happened to have my killawatt plugged in when I was working on my 7970,2x7950 and 7870 rig. runs about the same wattage with four gpus on maxcoin as with 3 cards on scrypt (previous reading was only one 7950, 7950 and 7870). So that is about one free gpu worth of electricity to run max instead of scrypt.
 
EarthDog said:
What a kill-a-watt shows is what you are paying for...

It could help to figure out actual power draw is, but you are paying for what's coming out of the wall anyway.
Click to expand...

I know what you pay is what comes out of the wall, but it's still useful to know efficiency of the PSU. Someone could try to replicate the information listed in the table and wonder why they can't get the same result...If it happens that PSU in the table is gold rated PSU and the person is using bronze rated PSU.
 
That's why I suggested to state what the rest of the setup was along with the PSU used.
 
nookuwn said:
I know what you pay is what comes out of the wall, but it's still useful to know efficiency of the PSU. Someone could try to replicate the information listed in the table and wonder why they can't get the same result...If it happens that PSU in the table is gold rated PSU and the person is using bronze rated PSU.
Click to expand...

87dtna said:
That's why I suggested to state what the rest of the setup was along with the PSU used.
Click to expand...
Good points, thanks! One thing to note is the difference will be small (bronze to platinum is 7%). So if we are working with a KW load, that is 70W (less obviously for lesser loads). Truth be told, a lot of that difference can be between different types of systems anyway. I don't know, I wouldn't put much stock in knowing that... but that is just me. :)
 
Edited my post above with efficiency on the Tt. At that load the difference between that and a gold/plat is probably going to be negligible due to such a small load value and being so far out of the efficient operating range for either.

First three cards are in, will post results soon as I get the rig up, probably this weekend or early next week due to work. Another 750Ti coming next week which will complete the rig.

3x750Ti really small crop.jpg
 
I think I'm gonna have to pick up a kill-a-watt soon... I keep seeing everything about 750tis being soooo efficient and I keep thinking I can destroy them with my army of 240s...

Man this is like benching but even more fun! And it makes some money!
 
I'm a serious noob at this here newfangled altcoin mining, but from what I've heard you would definitely crush everything efficiencywise with the 4GB 240s in some s-j algos.

I thought about that route too but want to be effective at regular scrypt coins as well as s-j, so hedging my bets with the 750Tis.
 
I don't see any value in bog standard scrypt moving forward, from a profitability standpoint. MAX, UTC, VTC, YAC, PTS, none of these are normal scrypt. That said, some of them act very similar to scrypt and can more or less be judged based on their scrypt rate equivalents (MAX and UTC to my knowledge).
 
LZ_Xray|3x750Ti|913kh|285w|3.20 kh/w

HX750
Z68MA-G45
Stock CPU fan is the only fan



Baseline from previous post. i3-2100 at idle, gpu removed, all fans except cpu fan removed, old pos thermaltake toughpower 750w psu. Display on and running from the i3 iGPU.

1jQKZoX.jpg

Changed psu to an HX750 and the idle only dropped 0.4w so not updating that. Here's 3x750Ti on the system running at idle. All cards detected. Turns out I can't run the iGPU and GPUs at the same time on that board, so display is running from GPU in slot1.

3x750Ti first start idle power small.jpg

And mining. Kinda optimized but think 0 and 2 will do better. 1 is a pig.


khashsmall.jpg
clockandtempssmall.jpg
mine load 3x750Tismall.jpg

Hash with the Chrome trick. I was surprised how much difference it made. Power went up 10w to 285.

hashwithchromesmall.jpg
 

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Nice one. Did you flash the BIOSes to stilt's? I have 2 pcie slots left and 7-800 watts of PSU. I am contemplating a couple of 290s, now that prices are starting to come down.
 
Yes. The only difference it made was that it allowed me to run higher core clocks for more hash. But, if I do that I have to increase voltage instead of taking it away.

So, they ran 830kh on the stock bios at 945mhz. On any other settings the hash went down. On the stilt, I run 950mhz for 835kh, I can hit 900kh at 1050 core clock but it uses 50+ extra watt per card. So it's not worth the increase.
 
Here's some food for thought: http://www.legitreviews.com/nzxt-kr...oler-review-on-an-amd-radeon-r9-290x_130344/5

Read the last paragraph. A 44 watt drop in power usage under full load and water cooling.
If you are running many cards like this, then there could be a chance these power savings will offset the cost of running the pumps and in turn, reduce your power used mining.

I wonder if all new R9's experience this... If so, watercooling might be in the near future for me.


EDIT: Oh and: Silver_Pharaoh|270x+7850|340watts|900Kh|2.64Kh/watt
 
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