Topic: Building a 6990 Rig - Operating System (Read 14928 times)

hi goldcd, i have the same setting, 2x6990 on w7 and i overclock with MSIafterburner at 900MHz but when i try to underclock the memory 779MHz is the lower value that i can set, if i try to set 625MHz the memory clock go in the default valute 1250MHz, why i can't put 625?

When I said that I meant memory clock can not be more than 100mhz below core clock... for example I upped my core clock to 940 meaning that the lowest I can go on mem clock is 840, If I how ever had 960 core clock and 840 mem clock, the mem clock will default back to 1250 due to being 110mhz below core clock. Yeah my 3 6990's got hot very hot so I removed 1 and run with 2 on windows using afterburn, windows structure only allows 4 instances of the driver to be loaded at the same time, something do with opencl, So no good for 3 x 6990(6 GPU's). If anyone does get 3 cards running at a decent hash rate(2000 MH/s + ) and keep the cards cool, then I will go back to linux, until then Im happy with 2 cards running at 1600 MH/s

edit: anyhow, thanks for the input. maybe 6950s are the same, because i can't get my memory clock down. gonna try going for coreclock-100MHz now.

edit²: nope, i can't underclock my memory.

Hey dude, nice workaround, I'm having trouble with my 3x6990's temperatures. I have one question, you mention that underclocking more than 100mhz of core clocks will default to 1250, so how did you manage to get to 840 in linux? or did you end up using windows and afterburner for good? thanks!

Hi Darkpandora,

Can you share with us how you managed to change the memory clock speeds in your 6990? I'm currently stuck at 1250 and nothing I do seems to untangle it. Please help if you can, thanks!

Regards,

Forsythe

Just to add some of my small experience with the 6990's using Windows, I set the clocks 920/840 and get just under 400 MH/s per core(just under 800MH/s per card) with fans set at a constant 90% the GPUs get around 70-75c except for GPU2 which is at 81c. I noticed when going lower with mem clock it actually gains heat (1-2 degree's). Also these is a switch near the crossfire port that will turn stock 830/1250 into 880/1250, I used afterburner to get the 920/840. Also something to think about is that you can not under clock memory less than 100mhz of core clocks(you can visually do it but the effectivness is zero and will reset your mem clock back 1250, at least in linux anyway). I did get over 405 MH/s by setting the clocks to 940/840 but didn't want the extra heat or didn't want to increase fan speeds above 90%. The temps are stable and barely move. I used Phoenix Riser with "vectors" "13 aggression" and use the "BFI_INT" as extra flags. I still need to tinker around with the fan speeds to see what effect it has when lowering them, but im happy with 2 x 6990's(I use to have 3 but got too hot under linux) which produces just under 1600 MH/s

However you can flash a 5850 into a 5870 but it's completly useless since that will not unlock the shaders.

Regards,

you can use atioverdrivectrl in ubuntu to set your 6990 clock to 1000,150. you get 850 Mhash/s

I suggest LinuxCoin all the way.
Free, from pendrive, up and running in minutes.

Then if you want to OC, edit your cards BIOS in 15 minutes.

Just to chip in.
I'm currently running 2x6990 cards.
Bought these with some very old bitcoins I had, so I'm looking at this as a free 'ninja game system' that make make me some money.

Firstly I'm running my two 6990 in crossfire mode under win7-64bit. I believe I might do better turning the crossfire off, but that involves dummy VGA plugs and my first attempt at those didn't work.

Two tips I have to give out to my fellow 2x6990 user:
1) Use MSI afterburner.
At core voltage I can get the Clock up 20 to 850 and reduce the memory clock down to 625. This not only gets the hash rate up a little, but reduces the power consumption down by well over 100W
2) Assign all processes to the same core on your CPU. E.g. Create a .bat file as follows:
"
start /affinity 1 /min poclbm.exe -d0 -w256 -f60 --host=mining.bitcoin.cz --port=8332 --user=?.?--pass=?
start /affinity 1 /min poclbm.exe -d1 -w256 -f0 --host=mining.bitcoin.cz --port=8332 --user=?.? --pass=?
start /affinity 1 /min poclbm.exe -d2 -w256 -f0 --host=mining.bitcoin.cz --port=8332 --user=?.? --pass=?
start /affinity 1 /min poclbm.exe -d3 -w256 -f0 --host=mining.bitcoin.cz --port=8332 --user=?.? --pass=?
Just underclocking the memory and assigning to one core got my power consumption down from over 900W, to just over 700W

I'm not for one moment suggesting this is the 'best' configuration, but it pulls in around 340 a core, which seems reasonably respectable.

As others have stated, it really is a matter of personal preference. Or money, if you don't want to spend $$$ on Microsoft.
Personally, I'm using W7 x64 because this is my main personal computer. I'm getting a steady 375-385 MH/s per GPU with mild overclocking. I did have difficulty trying to reduce the Memory Clock, so I have that set at 1000Mhz and the Core Clock at 900Mhz.

If you do decide to go w/ Windows, I recommend using MSI Afterburner (it does work on non-MSI cards):
http://event.msi.com/vga/afterburner/download.htm

I use the latest Beta version with success.
https://i.imgur.com/yJSH0.png

Also, the fan on the 6990's is LOUD. Very loud. I mean it's so loud that I can hear it next door in my neighbor's apartment...
They also run quite hot. I fiddled quite a bit with the fan settings in MSI Afterburner to get the fan speed as low as possible. If you do not do this, and just let the hardware set the fan speed automatically, it will alternate between high and low speeds and probably annoy the piss out of you. Here are the settings I use to keep the fan at a very stable 65-67%:

https://i.imgur.com/MF4wD.png


I keep my interior room temperature around 75ºF. Your conditions may vary.

I have a single 6970. In linux with worksize 128 and -v and overclocked to 950mhz, i only got 352Mhash.

Now I'm mining in Windows 7, with -w 128 -v and the like, overclocked to 950mhz and I am getting 412Mhash.

Go for Windows. The drivers are better and faster when it comes to the ATI cards.

Mining with one 6990, factory setting @GPU 830 MHZ, Memory 1250 MHz, 1.120V

Linuxcoin, Pheonix with poclbm

DEVICE 0: VECTORS AGGRESION=13 WORKSIZE=128 BFI_INT reporting 334Mhash/sec
DEVICE 1: VECTORS AGGRESION=13 WORKSIZE=128 BFI_INT reporting 323Mhash/sec

http://50.45.128.27/uimg.php?u=markietalkie



I hope I'm doing this right. If I'm doing it wrong, any advice would be greatly appreciated.

It's funny how this thread turned into a 6990 thread rather than an OS thread.

I had a quick question about the starting topic though heh. How much more stable is linux compared to windows in general? I'm currently running some dedicated mining boxes on windows and I am currently still working out the kinks of heat and whatnot, so I get about 1 crash per day.
Is that because of windows and I'd get better results in linux, or is my thermal / overclock too high and it's my fault? (running 3x 5870s in one box unspaced, OC'd to 975MHz, top card can getupwards of 90C, but I've also had occasional crashes in a spaced rig with temps closer to 80C).

I was running 2 6990s in a machine with the sames results.  Cores 1-3 would work fine - getting about 320 mhash/s.  Core 4 would see around 100 mhash/s.  I too was using poclbm.  Has anyone gotten 2 6990s fully working in one machine with windows?  If so, could you tell us the details?

@bahnfire or anyone else who can help:
What is your setup with the dual 6990's w/ Win 7?  If you would please give me some details as I'm trying to get mine where it should be.
I'm also using Windows 7 with Dual 6990's.  Currently I have them in crossfireX, using the latest poclbm and catalyst 11.5.  I've played around with several clock speeds, etc but nothing really make a lot of difference.
I have all 4 cores mining, but (3) are mining at 325mhs while the 4th is only at 100mhs.  Can anyone offer me some advice?
I'm using -v -w 128 --platform=0 switches.
(without --platform=0 for some reason everytime I started the 2nd core the whole machine would lock up)
Thanks

I have a dual card (4 core) 6990 system going 24/7. I am seeing between 1200-1400MH/s on deepbit. I am running Windows 7 x84, 4GB RAM, 2 unmatched 6990s (XFX and a Sapphire), and a watercooling kit.

I advise you go with Windows.  Much less of a headache.  I'm using 11.3 Catalyst drivers and Stream SDK 2.4 and at stock clocks I'm getting 307.5 Mh/s on each core.

I just set up a dual 6990 miner and I'm not having much luck with performance. I've tried both Ubuntu 10.10 and 11.04. Currently using the 11.3 Catalyst drivers and 2.3 stream sdk.

Here are my current rates running poclbm:

Card 1 - core is at just over 300khashes/s, core 2 won't run (Verification failed, check hardware!)

Card 2 - just under 90khases/s, though I've seen this card exceed 200k per core

I may have to give Windows a shot until there is better driver support for the 6990s.

Thanks.  That's good to know.