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I'm also setting up a 6 x 6970 watercooled rig and hope to get some good hash out of it. Can you down clock the memory as easily as the 5 series card in something like cgminer?

What kind of overclocks and hash rates can I expect? What kind of power consumption?

thanks.

My 6970s ran stable between 965 and 1015 engine clock speed depending on the card. Unfortunately, they had that factory limitation of only downclocking the memory 125 Mhz lower than the engine speed. I tried flashing the BIOS but the last few generations are hardware limited, not software so it had no effect (this is why I put the gpu-memdiff option in cgminer). With +20% powertune and engine speeds 15 below mentioned above (I wanted stability), I was getting 400-430 Mh/s. It has been estimated each card run like that would be 280-290 Watts. I ran 4 of them with a (very good) 1250 Watt PSU and no problems.

I would expect to burn up your power supply. I have 4 and its at 950 watts. Even with a 1500 watt psu it would be bad. You want to use around 50% of of your power supply to be efficient. I would recommend using two. I run mine at 950 mhz so I can use the pc without having crashes. 6970's are just a terrible choice for mining. I wish I never bought mine. I just leave the memory at 1375. There was no change in any temperatures when I lowering them. If you are using a good setup they should stay cool anyway.

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!

If you set them up properly, they really aren't.  A 5870 is certainly preferred, but they really aren't *that* far off from each other if you do it right.



I dropped 100 watts from a 4 card rig just with dropping the memory clocks to 340Mhz.  That heat has to go somewhere.

Sapphire reference cards. They most definitely need a hardware modification to allow setting memory clock lower. There were some links showing how to do so with some wire and solder and shit and I decided against it <_<

You're most welcome and thanks for donations =)

Bullshit.

Yes, you are most efficient at 50% but by no more than 2 or 3% it your PSU is 80+certified.
Any decent 1200-watter will pull 950W at the wall indefinitely.

As to leaving the memory at 1375, God help you. Even with the hardware-limited "core_clk -125MHz" cards you'd easily drop ±20 W per card. Less power, less heat, less PSU load.

Yeah, the link you're referring to about modification was to override the ROM write protection.  It's actually not enabled on any of the ROMs I've encountered (including the recent Sapphire reference 6970 boards), but the ATIFlash utility couldn't send the correct commands to unlock the ROM to erase it if it was flashed in a particular way.  For example, I had 6 identical XFX 6970s that I had purchased new & sealed from Newegg.  I was able to flash 5 of them successfully but the 6th appeared write locked (which required disassembly and a 1 wire solder).  To make things even more odd was that I could no longer flash any of the 5 cards after they had been flashed once.  I understand why it does it now, but I was originally baffled.  Now that ATIFlash has been fixed, I can flash any of the cards without disassembly.

Think of it this way -- the only way you wouldn't need a hardware modification to set memory clock lower is if they stripped the variable clock generator off of the board.  If they did this though, none of ATI's power management features would work properly (the cards scale the clock back when the card is idle or under low load).  All of the cards would be sucking down significant power at idle.

^all of this.  A bit harsh, but correct.

So.. you're saying a newer version of atiflash is all I need now?

It's called shock treatment. Just what the doc prescribes to guys with 30 posts under their belt authoritatively stating that a 1500W monster can't pull 950 Watts :)
My point wasn't to be harsh and nasty. I needed to stop the disinformation from being spread around.

Thank you all very much and I had seen some of your posts sveetsnelda which is why I decided to buy these. I got them for a good price and in the end, they do have good resale as solid gaming cards.

I'm thinking I might have to split the cards into two rigs though, 6 cards just sounds like a headache on one mobo. I have an extra msi 890 FXA-GD70 and a seasonic 750 watt. I'll maybe put three cards on that with a nice 360 rad since the cards came with blocks and then put the other three with a 480 rad I have and try to add a 5870 I have that won't let me control it's fan no matter what i do, bios flash, etc. just easier to handle
I have a seasonic 1250 watt for the 4 card rig also.

Or i could just get a 240 rad for the loop and that would give me a 480 and 240 for the 6 cards which should be fine.

I have the sli fittings for parallel, etc.

will all 6 cards work on an ASUS P8P67 WS motherboard with the right extenders?

So assuming I flash these and get the memclock's down, will this rig work?

ASUS P8P67 WS
6 ATI 6970's with swiftech komodo full waterblocks.
koolance 480 rad with high speed fans (sycthe ultra kaze 3000 rpm)
swiftech mcp 655 pump
swiftech resevoir
240 koolance rad to match i guess, 20 fpi fin density at least(scythe ultra kaze 300 rpm)
seasonic x-1250 gold
i3 2100 cpu, undervolted as much as I can get it
2Gb ram
pci extenders so I can use all the slots on the board.
16GB flash drive running linuxcoin and cgminer.

I believe so.  Took care of it for me.

Thanks... whenever my freaking motherboard is replaced I'll see about it :)

I have sapphire referenced 6970's, there should be no reason to solder or use atiflash. Lower the memory clock is simple but no very important. It won't be a noticeable heat difference. May as well lower it if the pc is only used for mining though. I was adding a new 5970 to a pc that already had 2 in it. And I could not get the voltage or clock speeds to change. I tried several cards and the newly added card would always refuse to change. I finally fixed it by removing all the cards, and running just the card that was giving me problems. It then overclocked fine, and when I put the other cards back in there all set to the correct clocks.
I've also found it very useful to use afterburner for overclocking and running the fans. A lot of people claim to have trouble with it, but if you do it right it works perfectly.

This is only if you're using Windows.  The ATI driver in Linux will not let you lower the memclock further than 125Mhz below core clock.

Very wrong.  Lowering memory clock will drop almost 25 watts (AC) per card and won't affect performance.

Yes there will.  25 watts of electricity = 25 watts of heat.  The energy has to come from somewhere.

Afterburner is Windows only.

I'll just do some math for our uninformed cuz0882:

OP is setting up a 6 GPU rig.
6 * 25W is 150W less of energy and heat. Still think it's not noticeable?

6970 are very hot GPUs. The 69xx family of cards are flawed products, having been meant to be manufactured at 32nm instead of 40.
Mind you, that it's supposed to be a water-cooled machine.
Removing such levels of heat requires a huge and expensive radiator complemented by a full battery of push-pull high-static-pressure fans and a very strong pump. I'm not sure even a 4*120 radiator will do the job with ease.
Since it's not going to be a walk in the park by any stretch of imagination, it is therefore crucial to minimize the heat footprint before the heat is transported away and dissipated.

Friendly suggestion: when posting on subjects you know little about it would be more appropriate for you to end your posts with a ? instead of a .

This new atiflash will work for linux, correct? It's one of those dos bios flash programs I assume. I usually have a hard time figuring out how to make it work, but I'll get it eventually.

I just want to be able to lower the memclocks and crank up the OC at stock voltage with cgminer like I do with my 5 series cards.

I'm building this rig for my dad and need it to be pretty stable so I don't have to go over there and work on it all the time.

Hell I can't see any stability issues with water cooling unless I go for a crazy overclock and I'm not going to do that. I jusy want some power savings with the lowered memclock.

I can reduce my 6970's mem to 300mhz (or lower) just fine with clocktweak- does this mean I have an unusual card?  Never did any BIOS mods or anything of the sort, just software OCing.

There is a reason cgminer reports back the CURRENT settings after you change it: It's because the driver will often accept a value you give it, but the hardware will NOT. So you may set it to 300 and it will merrily ignore you and set it back to the default. Try setting it to only 125 lower than the gpu engine speed and if it suddenly starts running cooler than when you "set" it to 300, that is what's happened.

Clocktweak is for Windows.  Changing the 6970 memclock in Windows has never been a problem.  Linux is the issue...

Guys, CKolivas knows what he's talking about when it comes to cgminer and since he says he wosn some 69xx series cards, you can take the rest tio the bank. Sveetsnelda is helping me with linux, not windows.

Also, just an update. I'm going with 4 6970's on the board with a 480 rad, nice standard, stable water cooled set-up. Got all the stuff cheap, so I really don't feel the need to "max" everything out. This thing is going to live at someone else's house and I suck at networking so don't even feel like dealing with remote access. So I need this thing stable as hell. I'm going to take the extra two cards and put them into my dad's already water cooled gaming rig. He has plenty of water cooling already set-up to handle crossfire and he's a gamer. So I'm going to set him up with a nice 6970 crossfire rig and sell his water cooled gtx 470. When he's not gaming he can crank up afterburner or whatever windows tool we use and start the miner to make a few bucks.

Should work out just fine.

Thanks for the help and I'll report back when I have it set up.

K, Cause i have a 6990, (yeah i know totally different in the hardcore aspects) and i can drop it's mem clock to 333 with the core at 925, Been running solid for 8months now

can u give me a link to this atiflash utility for a cgminer rig with Win7 with 4 6970's please?

ATIFlash 3.89 @techpowerup.com (http://www.techpowerup.com/downloads/2040/ATIFlash_3.89.html)

thanks Jake.

NP Cypherdoc.
Remember that the flashing utility will require admin rights and be sure to start with creating a backup of your old bios.
Best of luck.

thanks to you guys i'm now pulling 400 Mh/s per card :D

Is that bothering you?  ;)

Which bios did you flash your 6970 cards to? just use the newest one or one in particular?

Hey cyperdoc, may seem like a dumb question, but how did you back-up you old bios?  In what folder are they located?

Also, after downloading the flash utility, what exactly happens?

I guess what I really want to know is this:  What steps did you take from the moment you downloaded the flash utility to when you were able to successfully lower your mem clock to below a -125 differential?

The reason I'm asking is because it's a very expensive computer and I want to make sure I don't jack something up through trial and error.

Try that. (http://www.techpowerup.com/forums/showthread.php?t=57750)
Worry about the flashed card, not the whole machine. It's not like it'll blow up in your face or melt down.
Don't flash until you have made (and verified) backups of your existing BIOSes. Use ATIFlash's -s switch for that.

Can you please post the link? I have a Weller soldering station, and would want to experiment a bit.

It's in these forums somewhere but I would just be searching for it too, sorry, since I haven't kept the link.

hey joint; you and i are in the same boat.  i haven't done it yet cuz like you the links aren't quite clear.  luckily i'm getting that 400 Mh/s w/o the flash.

That's right where I'm at...400 Mh/s a card at 890/765 with +3 powertune, 95% fan with the hottest card sitting at right around 79C.  I'd feel much better if my hottest card was at 70C, or if I could at least drop my fan below 70%.  Sucks not being able to adjust the voltage either.

hmmm.  i use 950/850,  powertune +20 for both my machines.  the one with 3 Sapphires (2 very close) in a case turned on its side with cards vertical with the side panel off and an external fan keeps the temps @70C.  the other machine has 2 Powercolors with good separation with the side panel off with temps @79.5 and 73.5C

Damn, by your numbers I would think you'd be getting way more m/hash than I am.  +20 powertune?  Is that OK for a card?

so i've been told.

Cypherdoc, you got a kill-a-watt there?
Did the hash rate budge an inch when you went from 0 powertune to +20%? Did the temps rise?
The reason I'm asking is, some cards will just lie about powertune status. My asus reports success with every powertune value but clearly ignores it.

I had an absolutely massive rise in hashrate going from 0 to 5% (more than 5%). Going from 5 to 20, on the other hand, would make hashrates fluctuate wildly, but ultimately be the same average as 5%. So it seemed to be more of transient turbo boost  at levels above 5%, but since mining goes 24/7, it ended up being the same. There is no documentation about what powertune really does. Nevertheless, if you're well within good heat ranges, and powertune is available, it is *well* worth trying. To me it appears to increase hashrate proportional to the amount of power it it uses which is perfectly valid as far as I'm concerned. No, I don't have hard at-the-wall numbers to prove this.

Powertune simply sets a limit to power usage.  It was added because different applications stress the card differently, for example gaming running the card a full stock speed doesn't actually use as much power as running furmark at stock speed.  Default powertune tends to give enough power to mine at stock speeds (at least in my experience, on my one 6970), but if you are overclocking you might need a little more power budget.  I suspect that is why you saw the increase going from 0 to 5.  But once you have "enough" power, adding more potential power isn't going to give you any more performance, which is why the 6-20 range didn't show you any real improvement.

hey joint, made some progress.

downloaded MSI Afterburner beta and adjusted to 967/685 and it boosted me to 403-405 Mh/s.  left voltage at 1174 but could change it if i wanted.  any suggestions as to what level might help?

i modified the .cfg file for more underclocking but it didn't allow me to drop to 340  >:(

slowly but surely.

sorry no kill a watt meter.  i wonder if i should buy one...

Cypherdoc, I did a little more tweaking.  Bumped my clocks up to 920/795 with 5% powertune and I'm pulling around 405 mh/s also.  I must not have the right MSI Afterburner version because it won't allow me to voltage tweak and it won't let me bypass the -125 mem-diff.  What is the link to the Afterburner version you used?

Also, I tried messing with the intensity briefly but I didn't leave the adjustments on long enough to average it out -- I currently have intensity set at 9.  When I crank the intensity to 14 on cgminer, It shows around 410-415 m/hash, but I'm not sure if my efficiency is dropping.  I'll try leaving a single card at 14 overnight and see what happens.

you have to modify the msiafterburner.cfg file:  https://bitcointalk.org/index.php?topic=37271.0

if it doesn't let you save the mods you have to go into properties and give yourself full edit privileges.

i just downloaded the beta version and it worked fine. 

Cypher, I read the thread you linked, but how do I modify it?  It's .cfg and doesn't open like notepad.

right click on it, choose edit in Notepad, enter mods, then save.

I right clicked, went properties --> open with notepad --> adjusted "unofficialoverclockingmode =   2"  (was previously zero) -->  save (I have 'hide file extensions' unchecked)  and then opened MSI Afterburner.

It didn't work.  Where'd I go wrong?

Edit:  By "didn't work,"  I mean MSI Afterburner works but underclocking the memory does not.

Edit 2:  I might not have the Beta version.  When I downloaded to begin with, I clicked the top link on the left on this page:  http://event.msi.com/vga/afterburner/download.htm (http://event.msi.com/vga/afterburner/download.htm)  and not the link below it (i.e. I clicked on 'Download MSI Afterburner" and not "Download the Latest Afterburner Beta." 

did you put this part in?:

UnofficialOverclockingEULA   = I confirm that I am aware of unofficial overclocking limitations and fully understand that MSI will not provide me any support on it

No, I didn't, but I fixed it :)

I just downloaded the Beta version and switched "unofficialoverclockingmode" to =2.   Fired it up and now I got 685 mem clock :)

Now I'm averaging 410 413 m/hash on all 3 cards with 920/685, powertune +10, fan 90% on all 3 cards, intensity = 9, hottest card at 77C, coolest card at 67C

Thanks!
Not bad :)

413?  grrrrrr.

what voltage do you have it set at and what exact 6970's do u have?

The voltage is weird.  On card 0, the voltage is locked at 1.150, but on cards 1 and 2 the voltage is at 1.175.  I can't adjust the voltage on any of them still, even with Afterburner Beta.

They are all HIS Radeon 6970s