Negative.  The 6970 can have the memory clock changed easily with a BIOS flash.  I have 42 more recent cards all flashed with lower memclock and voltage.  There were problems with atiflash sending the correct commands to a certain ATMEL ROM though.  For a few of the cards, I had to pull them apart and temporarily short 2 pins on the ATMEL to disable write protection while the ROM was flashed.  This ATMEL chip was used on a lot of later 6970s.  Maybe you ran into this problem?  ATIFlash fixed this issue in 3.89:


With my XFX reference 6970s, I get 1580Mhash @ 683 watts on an OCZ ZX 1250W PSU.  (900Mhz/340Mhz @ 1.050).  They've been stable for months.  If this is a dedicated rig and you underclock the memory/undervolt the core, you can run 6 cards.  Definitely don't do this at stock clock/memory/voltage though.  Your PSU will hate you.


Totally unrelated -- thanks for CGMiner!  My mining operation would was so much more cumbersome before it existed.  Now that it's scaled up to 40Ghash, it would be a nightmare without it.  In fact, toying around with these 7970s has made me wonder how I dealt with it before.  I've silently tossed some donations your way here and there, but I said nothing because I wasn't looking for recognition.  Thanks for the good work!

There is definitely room for improvement. I'll have to look into the transaction history and see what can be done.
The size option allows you to specify how many records you would like to fetch from the server. This allows you to conserve how much bandwidth should use whenever opening the transaction history. The default, which is 15 obviously needs to be displayed. I'll fix that.

I wish you would have been, though.

Vertical orientation on the motherboard, FTW. Those raven cases are pretty spiffy. Venting heat out of the top makes a hell of a lot more sense than trying to work it out the back, past a bunch of things that are  sucking it up again.

Is there any space between those cards?

Take a good look at the pic of the case being used:
http://ck.kolivas.org/pictures/Mining/IMG_1048.JPG

(ignore the crossfire bridges, they've been removed).

All the heat in that case goes out vertically upwards with reference cards that blow in that direction.

The case fan underneath is 180mm (there are 2) and blows directly into the cards with no obstruction whatsoever when closed.
The PSU is not even effectively *in* the case, having its own section so not contributing to case heat nor having to suck any heat out of its own accord.
The back is massively ventilated as well.
The case is a full sized tower, not a mini or midi tower.
The cards have spacers between them as shown in the earlier photo.
All the cards have their memory underclocked to exactly 125 below their optimal engine clock speeds (the cards run engines from 950-1005).
The cards were ordered so that the fastest ones were put in slot 0 and 3 since they generated the most heat they needed the best ventilation.

cgminer basically ran in all its auto settings to keep the fans running optimal.
Virtually all GPU fans ran in the 45-75% range during winter and most ran at 85% in summer (none ever needed to go to 100%), yet the temps were targetted and kept at 75 degrees.
This is all I can remember offhand.


...All in all this is a purpose built rig with a lot of thought into making it work within a case, and the case was carefully chosen. It is not just components slapped together. It ran 6 months without a single hiccup. What *has* taken this rig down, though, is a dead motherboard. Not sure what I could have done to prevent that one though.

Great!

They're... pegs... as in clothes pegs, for a clothes line. I just pulled them apart. You get them... everywhere and these particular ones are made of... plastic.

I believe the standard defines 1.5cm of movement or something like that. This is only .5cm yet makes a massive difference to temperatures.

Heh yes it is. Great case for when it all must be in a case. The cards dropped a good 15 degrees or 25% fanspeed with those half-pegs.

As I told you before, I have no idea whatsoever how well cgminer does on Windows.
*shouts out loud* Ye Windows-miners attend, attend! A little support for cypherdoc here?

Yeah, what about that card? Other than the fact it's burning up alive, that is.
Post me the Afterburner settings for that card, there might be something wrong with fan speed or the card could just be suffocating due to being physically to close to the other cards.
You should keep at least one empty slot between the cards to let the fans breathe.
If you really can't, do what Conman did.

EDIT::Kill crossfire. Not only do you not need it, it is detrimental for the hash rate.
EDIT::Actually, in the case of my case, the temperatures dropped slightly with the side fan blowing in due to (relatively) cold air being blown in where it's most needed.
        You still need excellent exhaust, though, to get the hot air out from the case ASAP. I upgraded my exhaust with two Noiseblocker 140mm 1700RPM fans.
        If your exhaust fans aren't strong enough, feel free to give that side-mounted fan a try in exhaust configuration.
        The question is, when you open the case do the GPU temperatures rise or drop? If your airflow is good enough, the temps should be lower when the case is closed.

Nicely done!

Yeah, I ment precisely that I don't read minds. I know what a min value means, I just can't know what the numeric value corresponds to the min setting
e.g. you said voltage was at min. Great, but I still don't know whether that is 0.6V, 0.9V, 0.95V or 1.1V.

In undervolting discussions, negative values are being used as a distance (or delta) from the stock core voltage.
If the stock voltage for a particular GPU is 1.100V then -0.020 means core voltage of 1.080V.

It looks like you've got this particular 6970 GPU set up quite nicely. Which is it BTW?
0.820V core voltage is looking nice indeed.
I don't think you can move the Shaders Clock slider - on current AMD cards it's using the came clock as the core. Just ignore that.
Memory is decent at 685, a lot better energy- and heat-wise than 1375MHz.

Once you get the rest of your cards nice and cozy, there will be some overclocking to do.

Can you post the settings screens for your other cards as well?

Cypherdoc, do keep in mind I'm not a psychic. Instead of just saying "at min" do add the numeric value, k?  

Do you think you could compile a table like this?

The only thing I can say for sure is that you successfully dropped the memory clocks and that you desperately need better ventilation or will have to start dropping core clocks.
Over the long haul, those fan speeds and temperatures are not acceptable.

Are those non-reference cards?

 If they are, there is a possibility that the manufacturers cut corners and equipped them with a non-adjustable VRMs.
Can you post the model numbers of your GPUs? Or links to the manufacturer's site showing the precise model?

Do you think you could post a decent photo of the whole set up?
That would give me an idea as to what those cards actually are and where some additional fans could be McGyvered in for better airflow.

cypherdoc: You should be getting close to 400 MH/s