Topic: 3 x 6990 mining rig, need help (Read 2234 times)

Any chance I can revive this thread? There seems to be good info here with knowledgeable people.

I'm trying to run 3x6990's on my rig as well but I'm getting strange results

Sempron 140
Corsair 1200W (CMPSU-1200AX)
2x1GB RAM
Driver 13.12
SDK 2.9
CGminer 3.7.2
Win 8.1 x64

I'm currently running two just to see if I can make this work (and to rule out the PSU).

I can't raise the intensity of my cards past 11. When in 12, it will mine for a few hours, then just stop. Anything higher and it will last only about 2 mins.


What happens is that cgminer is seemingly doing fine for a minute or two, then all of a sudden the program freezes and CPU usage goes all the way up to 100%. No "ghosting" on the cgminer window or any error messages.

Windows itself doesn't completely crash but it becomes pretty unusable. If you move the mouse, you don't see the pointer move all the way, you just see it jump from place to place. Any input (keyboard or mouse) in this state takes about 20 secs to happen.


My batch currently is
cgminer.exe --scrypt -o stratum+tcp://uswest.wafflepool.com:3333 -u 1663f2rW79j9chkvwt783qv52ifEN7hDaP -p x --thread-concurrency 8192 -g 2 -w 1024 --temp-overheat 80 -I 11

It was mentioned by rocketron that I should NOT let CCC install but I can't figure out how to do that.

Suggestions? Comments? Concerns? Consolations ? Anything is greatly appreciated.

hold on sec, that psu has 8x12v rails with up to 120amps!!! each rail is 25amps

"class-leading eight +12V rails with 110A (Peak up to 120A)
-That's a lot of rails, but then again 110A is a lot of power"

theres nothing wrong with your psu m8, thats a very good one! and well capable of running 3x6990s

I didn't know my PSU wasn't decent..score 9.7/10
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=175
I will look for a second PSU of 450 W or something.

get yourself a decent psu then, something like corsair ax1200, or the evga supernova is a great psu

It's NOT the watts, I have plenty of Watts.
It's the Amps for each 12V line. I only seem to have 4 12V lines.

the specs are quoted by manufacture for a recommended powersupply, not for actual power usage used by the gpu's! this is the misconception about powersupplies

wattometers do not lie!

heres a screenshot of the onboard power meter on my axx1200i for 2x 6990s

https://www.dropbox.com/s/jkzvbi07wkhnzqh/psu.JPG

1500 watt psu is more than enough for 3x 6990s

Ok, then tell the companies that created his GPUs that THEIR specs are wrong, I am telling him the factory recommended system requirements for his make and brands for solo and crossfire set-ups.

your wrong on specs,

my rig pulls 785watts from the wall according to me meter, 2x 6990s, so for a 3rd you can add about 350watts. so his psu is fine

They are correct. Your GPU's require 750w each for minimum requirements (1000w for crossfire setup) which means your GPU's alone will need between 1750 - 2250w and then your sempron needs another 45w.

According to someone it's my PSU

Which PSU did you use?

Why is that?
I have only 3 x 6990



Shit looks like that i'm on AMD 12.8
I'll try 13.11 now.

in my opinion you need 16+ for 4 6990s

Hello

Thanks for your message.

I have upgraded the ram from 2GB to 8GB.
Still not enough?

cgminer will crash if you use too high of thread-concurrency and not enough ram to support the threads.  The reason why 8192 worked with 2 cards is because you are using less memory with 2 cards.  Adding two more gpu's with the thread-concurrency at 8192 and you are over allocating memory and cgminer wont start.  Simple as that.

Either run lower thread-concurrency with 6 gpu's or get more ram...

Also, you might benefit from reading about the internet.  All this info is freely available

could also be your cpu not providing enough bandwidth to run the gpus, bear in mind I am running on X79 with a I7 3970X

Yes i'm in the same mode...
Grrrr 

aslym mode 880 mhz bios

By the way, BIOS switch 1 or default?

So you got 3 x 6990 running in windows with above settings?

I think i will switch in linux to give that a try.

Yes Catalyst 13.1 without CCC, Cgminer 3.7.2, SDK 2.7

For some reason, it only accepts low settings. Thread concurrency above 7500 = crash or no nothing happens.
Same for intensity above 17.
So i'm stuck currently with 2800khs for 3, which is not too bad..but I was getting +2KHS from 2 cards .
I'm now also getting a few HW errors..

i am out of ideas dude, what version of cgminer are you using? try 3.7.2