Best Hash/Watt GPU Setup, Undervolting

[ivanlabrie]

@carly200

i made accurate counts.
results for R9 280x are very different from the results of 7950.

in my counts, 7950 is preferable to run undervolt like my own, if day profit is under 11.09$ per Mhs
instead, for R9 280x is preferable to run undervolt only if profit day is below 6.69$ per Mhs

for this counts i use this data:
hd 7950  (mine) undervolted @ 520 khs per 135w, overclocked @620khs per 275w
R9 280x (the one of a friend rig) overclocked @760khs per 308w, undervolted @575khs per 153w (take data from the "save money 7970 thread" here)
costs of power: 0.2443 euro kWh. (i pay this in Italy)

A 7950 draws 160w undervolted at 0.962v...and pulling 660-700kh/s with an optimized bin file and sgminer.
You should read this thread: https://litecointalk.org/index.php?topic=12369.0

i know "theStilt" thread. i have optimized CL file for sgminer 4.0.0
i not use for now special bios whit mem optimized by theStilt because i just use memclock @800 which is a right optimized step.
i will try to run my 7950 at 660/700 (my max was 630) and i will try those bios, if really consumption is 160w, that is wery better than my actual setup. i will see and report.

I've tried it and 620kh/s was at 160w with 0.962v. 660-700 would make it draw slightly more, but it will still be around 180w max.
I'm in the process of switching to R7 240 4GB cards, and some nvidia stuff for yacoin, ultracoin and variable N factor coin mining (scrypt asics will make the old school radeons useless...they are not so good at scrypt-jane and draw 10x the power the r7 240 draws...)

At the wall I get 20% more cause of the psu btw.

[crazyates]

We got a batch of GB 280x with nice ASIC quality, and we were able to undervolt to 1.01V @ 1040/1500 for 720kh/s. Each card was pulling ~205W from the PSU. Total draw for the whole 5 card rig was 1250W on two 80Plus Gold PSUs.

Since then we've slacked off our undervolt, overclocked a bit more, and with The Stilts BIOS we're getting 745kh/s @ 1.05V.

[DeadMan3000]

Hi. I am about to drop some cash on a small setup. I was going to get the Sapphire R9 290X Tri-X OC which is about £448 in the UK. Since I am relatively poor I need something that is going to get me a good hash rate with lowest power use. Enough to still be profitable on stuff like Doge etc.

Should I go for this card or a 280x/290 (brands and models please)? 2 perhaps if cheap enough? I am also getting a 1000w brand name PSU so that needs to be taken into account too.

I will probably be buying tomorrow so need an answer ASAP.

Thanks.

[ivanlabrie]

Hi. I am about to drop some cash on a small setup. I was going to get the Sapphire R9 290X Tri-X OC which is about £448 in the UK. Since I am relatively poor I need something that is going to get me a good hash rate with lowest power use. Enough to still be profitable on stuff like Doge etc.

Should I go for this card or a 280x/290 (brands and models please)? 2 perhaps if cheap enough? I am also getting a 1000w brand name PSU so that needs to be taken into account too.

I will probably be buying tomorrow so need an answer ASAP.

Thanks.

I'd reccomend a yacoin mining setup, using 4-6 Radeon R7 240 4GB cards in a Z87 G45 board paired with 8gb of ram, a 500w good quality psu and a celeron g1820.

Said setup draws 200w from the psu and pulls off 16kh/s mining yac: http://explorer.yacoin.org/static/calc.htm

[carly200]

280x can be the best efficiency wise.
my own experience:
280x toxic: 755kH@220W
280x dual-x: 710kH@230W
270: 478kH@170W
290: 895@330W (hash goes from 892-905 and power draw from 280-330)

(those values are calculated/measured "at the wall", so PSU requirements may be slightly below)

if you need blower style cooling, then 290 is the way to go.
if you are using risers and have ample cooling/space, then 290s give great power density.

if you want to go "small", maybe try a 4 card 270 setup. it is easier to handle (price, cards, PSU requirements, heat, noise)
a 270s setup may be a perfect compromise...

actually I am going to try a 4x270+1x280x setup soon. but since I only have a spare 1000W PSU (multirail), it may not work...

[ibinsad]

280x can be the best efficiency wise.
my own experience:
280x toxic: 755kH@220W
280x dual-x: 710kH@230W
270: 478kH@170W
290: 895@330W (hash goes from 892-905 and power draw from 280-330)

(those values are calculated/measured "at the wall", so PSU requirements may be slightly below)

if you need blower style cooling, then 290 is the way to go.
if you are using risers and have ample cooling/space, then 290s give great power density.

if you want to go "small", maybe try a 4 card 270 setup. it is easier to handle (price, cards, PSU requirements, heat, noise)
a 270s setup may be a perfect compromise...

actually I am going to try a 4x270+1x280x setup soon. but since I only have a spare 1000W PSU (multirail), it may not work...

here https://docs.google.com/spreadsheet/ccc?key=0AlhSF602y9DSdHRneWVZcjJLWmhjaVBMTHVCR3l4eHc&usp=sharing#gid=0
it shows
the 290 do 850kh/s at 250Watt is it right ?
It seems high Kh/Watt.

[carly200]

my 290s make 890-900kH@320-340W (at the wall)

[ibinsad]

my 290s make 890-900kH@320-340W (at the wall)

so if you downvolt you will not get 850@250W ?

[Wipeout2097]

280x can be the best efficiency wise.
my own experience:
280x toxic: 755kH@220W
280x dual-x: 710kH@230W
270: 478kH@170W
290: 895@330W (hash goes from 892-905 and power draw from 280-330)

At what voltage are they running?

[carly200]

toxic at 1.068 (driver)
280 dual-x 1.188 (had too many crashes with lower voltage) default

270 dual-x back to default (don't know 1.188?)
290s with original bios and undervolt in AB (1.109-1.117, 1.086, 1.086, 1.094)

those are all I can check right now...

[Starscream]

My own R9 290s eat about 275w each and produces 870KH/s (stable 800wu).

[carly200]

well, take of 10% PSU efficency, and keep in mind that mine are air cooled on board, so they run at 80-90°C that adds a lot of draw!

[ibinsad]

well, take of 10% PSU efficency, and keep in mind that mine are air cooled on board, so they run at 80-90°C that adds a lot of draw!

So between
290 tri-x and 280x toxic

you prefer toxic for temperature and less hw errors ?

[carly200]

no card should give HW errors, if it does your settings are wrong...

I like the 280x toxic, because 280 is a great architecture, and the toxic is the best 280x card (in my opinion).

it is a powerdrawer though if not properly undervolted!

[ibinsad]

no card should give HW errors, if it does your settings are wrong...

I like the 280x toxic, because 280 is a great architecture, and the toxic is the best 280x card (in my opinion).

it is a powerdrawer though if not properly undervolted!

If you have to decide between 280x toxic or 290 tri x and 290 cost just 50 dollars more, which you choose?

[Starscream]

no card should give HW errors, if it does your settings are wrong...

I like the 280x toxic, because 280 is a great architecture, and the toxic is the best 280x card (in my opinion).

it is a powerdrawer though if not properly undervolted!

If you have to decide between 280x toxic or 290 tri x and 290 cost just 50 dollars more, which you choose?

290... 50$ for 100 KH/s is a no brainer.

[carly200]

no card should give HW errors, if it does your settings are wrong...

I like the 280x toxic, because 280 is a great architecture, and the toxic is the best 280x card (in my opinion).

it is a powerdrawer though if not properly undervolted!

If you have to decide between 280x toxic or 290 tri x and 290 cost just 50 dollars more, which you choose?

290... 50$ for 100 KH/s is a no brainer.

that depends on the base price! lets look at kH per Dollar

280x toxic gives me 760kH ->  760/$400=1.9, 760/$450=1.68, 760/$500=1.52

add 50 dollars
290 tri-x might give 900kH -> 900/$450=2, 900/$500=1.8, 900/$550=1.63

290 wins.
my opinions
it depends on the setup, I run many 290 cards, but the 280x is the best, so if it is a single/dual card setup, I might go for the toxic. cooler more efficient and less noisy.
the 280x toxic (might even go with the tri-x, is cheaper) is a great (maybe the best card), the 290 tri-x is almost reference with better cooling, but some people report problems...