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Topic: Undervolting 69XX series (Read 5241 times)

sr. member
Activity: 274
Merit: 250
March 29, 2012, 07:59:51 PM
#12
I`ll did 3/4 of my planned work.
I have flashed seccesfully 6970 - mem@150 and [email protected] - i hope.
6990 gave me strange ERROR.
atiflash -p X nameofthebiosfile.bin -fs -fa -fm -fp
"EPROM not erased" if i remember correctly....

Bios switch on card is covered by sticker of somme kind with "CHECK USERS MANUAL" on it, but manual says nothing.
I`ll dig more on the web and try tomorrow.

EDIT:
aprox 50W power loss: mem 770->150 and 1.167-> 1.1
I changed CPU A64 6400+ (!!!!!) -> sempron 145
summary rig was taking 1050 from the wall, and now it takes 930.
5870-5850-6990-6970
sr. member
Activity: 274
Merit: 250
March 29, 2012, 01:30:18 AM
#11
i`ll try to grab somme bioses from my 6970 and 6990 today for testing...
Maybe it will give me somme power consumption loss.
sr. member
Activity: 472
Merit: 250
March 28, 2012, 09:21:02 PM
#10
I've been fighting with my 3 6870s over these same issues. At this point I've tried ATI tray tools, Trixx, CGminer, and CCC. None of them will adjust the voltage and I'm stuck with the memory 100 mhz below the clock speed. I was having heat issues until I pulled my wireless card and added an extra 80mm that I had laying around. I'd like to be able to drop the memory and voltage though to increase efficiency. I'm going to try afterburner next and see if that will unlock them.
sr. member
Activity: 274
Merit: 250
March 27, 2012, 04:12:21 AM
#9
You can mine with those settings: 700/575 - mem cannot be less than core-125Mhz. Works for me.
I cannot change V in cgminer Sad
no other tool for that....
full member
Activity: 136
Merit: 100
March 26, 2012, 10:22:45 PM
#8
I tried underclocking my 6950 with MSI Afterburner, but it seems the memory will not underclock at all. At 1v and 700/1250 mhz the card is mostly stable but sometimes rarely it hangs up. I'm running it at those speeds with 1.025v, seems stable so far. Load temps dropped a good 10c (using a scythe cooler + noctua fan).

At 0.975v the card ran fine for about a day before locking up. At 0.950v it locked up outright when I launched a game.

I'm aiming to reduce my power bill as much as possible, without having to part with this awesome card and without giving up too much of its performance.
legendary
Activity: 3472
Merit: 1724
March 26, 2012, 07:03:54 AM
#7
I have a box with 2x6990 and 1x6970 on stock BIOS, running at:
500MHz core / 450MHz memory @ 1.0V for the 6990s
500/400 @1.0V on the 6970

1120MH/s - 480W at the wall.  Oh, and having fans running below 40% is nice!  Smiley

There is another small voltage step to 0.95V if you drop all the way down to 275/150, but I saw not reason to run that low.

At such a low clocks you should be able to reduce the voltage much, much more.
Not sure which software will work though without BIOS flash but you can give a try to all the tools available.
For me barelyclocked works well for undervolting/overvolting all cards.

HD 6770 - works 24/7 stable @ 775/180 with 0.82V (stock was 775/1000 and 1.125V). This way temperatures decreased by 27C (the card is in a very hot place).
full member
Activity: 173
Merit: 100
March 24, 2012, 02:04:33 PM
#6
I dont know about 69xx as I don't have one. I'm assuming the 69xx also act like the 68xx. The 68xx will auto-adjust its voltage depending on the core clock.

Voltage range that will auto-adjust: 0.95-1.175 (can overvolt using Trixx but cannot undervolt)

6870 @ Core:
776-up = 1.175v
601-775 = 1.1v
401-600 = 1.0v
150-400 = 0.95v

Using CGMiner 2.3.1.2 Intensity 6:
950/134 = 310MH/s (Athlon II X4 + 2x 6870 + IGP as primary display = +/- 350w)
775/134 = 248MH/s (                             "                                  = +/- 270w)
600/134 = 195MH/s (                             "                                  = +/- 200w)
400/134 = 125MH/s (                             "                                  = +/- 145w)

I play online games with the IGP (900 core) while mining. Motherboard is Gigabyte 890GPA-UD3H.

* The power readings are from the wall excluding the monitor, while an online game called Granado Espada is running minimized in the background.



 

full member
Activity: 136
Merit: 100
March 22, 2012, 07:43:26 PM
#5
I'd wager Afterburner, since custom clocks are blocked by the driver.

I'm interested in your wattage too, I run a 6950 and it would be nice to cut back on the electric bill. It's for gaming though, so memory runs at full clocks.
sr. member
Activity: 274
Merit: 250
March 22, 2012, 06:16:34 PM
#4
You undervolt by bios or by afterburner or cgminer ??
whats the wattage of that card with that configuration ??
legendary
Activity: 1284
Merit: 1001
March 22, 2012, 05:02:08 PM
#3
I have 2 6950 that I run at 758/150 MHz, 0.95v, fans at 30%, and I get about 335 MH/s from each. They've been running like that since last summer, so they're pretty stable.
sr. member
Activity: 285
Merit: 250
Turning money into heat since 2011.
March 21, 2012, 07:16:23 PM
#2
I have a box with 2x6990 and 1x6970 on stock BIOS, running at:
500MHz core / 450MHz memory @ 1.0V for the 6990s
500/400 @1.0V on the 6970

1120MH/s - 480W at the wall.  Oh, and having fans running below 40% is nice!  Smiley

There is another small voltage step to 0.95V if you drop all the way down to 275/150, but I saw not reason to run that low.
hero member
Activity: 535
Merit: 500
March 21, 2012, 04:07:18 PM
#1
Read a few threads but didn't feel like there was a definitive method to undervolt these cards. I have 2 6970's and two 6990's in a machine right now and would like to increase their efficiency as much as possible.

Looking for lowest stable voltage no matter what the clocks need to be and of course lowest possible memclock.

I'll post what I can if I get anywhere on my own.
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