Topic: 3x7970 Mining Results. - page 8. (Read 61686 times)

Yep.

Just wondering if you can verify these numbers were on a 4x 7970 setup?  I might have to go buy if it is....

Ah.  Well, the PSU isn't making much of a difference then.

I have a corsair AX1200. Has about 90-92% efficiency through its range.

^This.  Also, I have no idea what power supply the OP is using.  If is PSU is heavily loaded, efficiency will drop.  I was using a Seasonic X-1250 which is built incredibly well.  It's rated for 104A on the 12V rail alone.  Me only loading it 50-60 percent makes things that much better.  ...not to mention that the PSU is just efficient in the first place.

160W lower idle. Replace heavily overvolted OCed PhenomII with undervolted AthlonII or Sempron and you're mostly there.

You achieved this with 4x 7970?

That is incredible.....720 MH/s per card?  the 7990 is going to slay all comers if this is the case.  A single card pushing 1.5 GH/s. 

Fascinating! That's with 4x 7970?

Even with similar clocking, you are pulling 50% better efficiency than the OP! You added an entire extra card, and dropped more than 100 watts. How???

And for those of you with cheap electricity:

2486 Mhash/sec @ 793 watts -- 3.13Mhash/watt  (1056mV, 1075Mhz/200Mhz).  Stable.

Also, idle wattage was 110 Watts with 4 cards.

Here are some results so far on a dedicated miner:

ASRock 870 Extreme 3 R2.0
Athlon II X3 455
Two cores disabled
CPU voltage dropped by 0.1V
1 stick of DDR3 1066
Seasonic X-1250 PSU (80 Plus Gold)
Windows 7 64 bit
60GB Vertex 2 SSD

All of my dedicated miners are usually using a headless Ubuntu install on a flash drive, but since there probably aren't any programs for Linux that will allow me to change the clocks/voltage on these cards yet (besides what's allowed in aticonfig), I'm using Windows to test this.

2202 Mhash/sec @ 583 watts -- 3.77Mhash/watt  (962 mV, 975Mhz/160Mhz)
2106 Mhash/sec @ 553 watts -- 3.80Mhash/watt  (949 mV, 925Mhz/160Mhz)
2134 Mhash/sec @ 528 watts -- 4.04Mhash/watt  (931 mV, 925Mhz/160Mhz)  (one of my cards will not stay stable at this voltage though.  The other 3 are solid.)
2060 Mhash/sec @ 498 watts -- 4.13Mhash/watt  (918 mV, 900Mhz/160Mhz)  (all cards stable)

If you still think these cards aren't efficient, you're drunk.  If they were still using VLIW, they'd be insane at hashing.  All GPUs show 99 percent utilization.  If small improvements can be made to the miner kernels, efficiency will be further improved.

I've got a small external fan blowing on the rig (as with all of my mining rigs).  The temps on these cards while mining at 2060 Mhash/sec are 63/64/65/61C.  The fan speeds on auto are adjusting to 30/30/30/27% respectively.

All wattages were read with a Kill-a-watt (which makes the measurements on the AC side, of course).

how do you choose a card then?  

imho to compare cards it is essential to benchmark them as separate from the system as possible. of course in the end it comes down to the whole rig. but it is irrelevant for the efficiency of the cards if I e.g. connect a heater to my powersupply.

OP, what tool did you use to undervolt your cards?

A card without a system performs at 0 MH/s/W. The only valid comparison is a complete system.

3200 stream processors vs 2048.  That's what matters the most no?  Dual chip cards are a little more efficient than two separate cards.  You gain by getting rid of duplication. 

OP's system uses lots of power but performance per watt for cards only is higher than for any other gpu.  ~3.9MH/s/W vs. ~2.3MH/s/W 5970

Because it is the reality of the situation on the ground right now.

If you have $3K to build some GPU based rigs you essentially got 4 choices.

1) 5870 (use 4 to 6 cards per rig)
2) 5970 (use 3 or 4 dual GPU cards per rig)
3) waste your money on 6000 series junk
4) buy a brand new 7970

Who cares what the apples to apples comparison will be in 2-3 months.  In 2-3 months people will evaluate what is available at that time.

The reality is which capital investment gives me the best return.  Period.

The fact that it is a dual gpu or single gpu is irrelivent.  The FPGA boards have both dual and single chip designs.  It would make no sense to say board X is the BEST (except if you look at dual chip boards) or vice versa.

My electricity costs are pretty high, so I'm very interested in efficiency.

I tweaked my setup a little more today to get my temps down. With 2x 5970, 675 MHz, .95V = 1172 MH/s @ 412W = 2.84 MH/W. That's about the best I can do without switching to 3x cards in a larger case.

The new cards are using a new process. We were expecting that the drop in process size would increase hashing efficiency significantly. It's very disappointing seeing the new cards barely hold their own against a 2 year old card when comparing performance per watt.

A MH/W comparison is not dependend on the number of GPUs I think.

Dia

I can't wait for the 7990s!!  I'm already saving for a couple of them