7970 hash rate reduced when 2nd card enabled

[pccs]

INFO:
OP SYS: Xubuntu 12.04
AMD APP SDK 2.8 - same result with 2.7
CGMiner 3.0.1 - same result with 2.11.3
Catalyst: 13.3 Beta - same result with 12.8

GPU 0 is primary display, with monitor attached.
The computer is still very usable, running CGminer now while typing this.
Am I missing something in CCC maybe?

Output GPU 1 only .... 720K ! ... Stable
 GPU 0:  52.0C 3321RPM | OFF   /610.9Kh/s | A:73 R:1 HW:0 U: 18.76/m I:13
 GPU 1:  65.0C 3350RPM | 720.5K/671.5Kh/s | A:71 R:0 HW:0 U: 18.25/m I:13


Output GPU 0 only .... 680K   ... Primary display with monitor.
 GPU 0:  65.0C 3309RPM | 680.9K/588.7Kh/s | A:206 R:2 HW:0 U: 18.91/m I:13
 GPU 1:  30.0C 3358RPM | OFF   /328.6Kh/s | A: 93 R:0 HW:0 U:  8.54/m I:13


Output Both GPUs enabled .... Both hash rates fluctuate from ~660K to ~690K!
 GPU 0:  66.0C 3292RPM | 678.2K/595.2Kh/s | A:232 R:2 HW:0 U: 17.61/m I:13
 GPU 1:  56.0C 3331RPM | 679.6K/300.5Kh/s | A:100 R:0 HW:0 U:  7.59/m I:13
--------------------------------------------------------------------------------

CGMiner settings:
"intensity" : "13,13",
"worksize" : "256,256",
"kernel" : "scrypt,scrypt",
"thread-concurrency" : "8192,8192",
"shaders" : "2048,2048",
"gpu-engine" : "1050,1050",
"gpu-memclock" : "1500,1500",
"gpu-fan" : "0-85",
"gpu-threads" : "2",
"temp-cutoff" : "80,80",
"scrypt" : true,
"kernel-path" : "/usr/local/bin"

[crazyearner]

Not forgetting 2nd gpu with moniter on it will run less anyway with monitor connected.

[pccs]

After 8.5 hours .... averaging ~680K per card.

I will try with only 1 thread and see if that helps.


cgminer version 3.0.1 - Started: [2013-05-06 02:31:50]
--------------------------------------------------------------------------------
 (5s):1.332M (avg):1.363Mh/s | A:18437  R:1260  HW:0  U:36.6/m  WU:1213.7/m
 ST: 2  SS: 0  NB: 213  LW: 3968  GF: 5  RF: 0

 Block: 9e5320ebb74bbad2...  Diff:26M  Started: [10:50:11]  Best share: 1.81M
--------------------------------------------------------------------------------
 [P]ool management [G]PU management ettings [D]isplay options [Q]uit
 GPU 0:  67.0C 3290RPM | 678.3K/683.0Kh/s | A:9188 R:631 HW:0 U:18.26/m I:13
 GPU 1:  62.0C 3352RPM | 670.8K/680.9Kh/s | A:9252 R:629 HW:0 U:18.39/m I:13
--------------------------------------------------------------------------------

 

[pccs]

Tried with 1 thread and different concurrency .... average about 500K

In Catalyst Control Center I am set up for single display multi desktop.
When I change that to single display only CGMiner will not see the second card.
I get the error that OpenCL sees more cards.

[computerparts]

This could be an indication of inadequate power. What power supply are you running?

[pccs]

PSU is 1200W ... plan on adding 2 more cards later, don't think that's the problem.
Power tune does nothing for me and I can't increase Intensity higher than 13 or the hash rate takes a nose dive.

I got it up to 700K avg on both cards. I stopped some background processes that I don't need.

[GenTarkin]

WHAT PSU is it? like model / manufacturer?
If its a cheap PSU, expect your rig to blow up in ur face
If its a 250$ + PSU, then yes it should be ok.

[pccs]

The PSU is a NZXT 1200W ... running good so far.

I think I need to boot ubuntu with the minimum XFCE processes and I will be in the 720K+ range.

What do you think of the NZXT PSU? I never heard of them before but it is "Gold Rated" lol.

[Ryu.Hayabusa]

NZXT isn't the greatest.  I'd only trust Seasonic or Corsair for running near or at full load 24/7.  Keep in mind some of these power supplies aren't so nice when they go and can take out other components with them.  With 2 cards you're probably doing I'd say around 750w total, so it shouldn't be a huge concern.

[cdog]

Intensity 13 sounds low, but Indeed it sounds like some issue with power draw at the PCIe slot... so maybe mobo issue.

Sounds fairly trivial in the big scheme of things, I dont lose sleep over these little issues its not worth it...

[pccs]

Not sure why I can't go over intensity 13. Maybe I need to try different versions of CGMiner....SDK...CCC etc.

All the hardware is new and I shouldn't be stressing a 1200W PSU with only 2 cards.

[Big Daddy]

Hi,

did you ever get it figured out?

I posted a couple of days ago (https://bitcointalk.org/index.php?topic=240174.0) looking for help on a similar issue.

I was running two cards in the 715 to 720 range, added a third on a riser and the best I have been able to eek out is 500 or so per card.

Any help you can provide would be most appreciated.

[phrozenspite]

a few questions, how much system ram do you have and is it a 64 bit os, with scrypt and 2 big gpus you might be running into system ram related issues.
do you have a dummy plug on the other card?
and do you have crossfire enabled? you want a dummy plug on the other card so that it thinks its connected to a monitor, and crossfire hurts performance

[mullick]

Check your PSu +12v rails. If you have  multiple and are running both cards on one rail separating between 2 may be the answer

[ohiwastedmylif]

anyone on here know if I x-fire a 7950 with a 7970 for gaming purposes if the 7970 will be throttled down to the rate of the 7950? Or are they independent?

[phrozenspite]

a few questions, how much system ram do you have and is it a 64 bit os, with scrypt and 2 big gpus you might be running into system ram related issues.
do you have a dummy plug on the other card?
and do you have crossfire enabled? you want a dummy plug on the other card so that it thinks its connected to a monitor, and crossfire hurts performance

Check your PSu +12v rails. If you have  multiple and are running both cards on one rail separating between 2 may be the answer

may want to check who you quoted, since i wasn't asking for help here.
and to the guy who just posted... do not crossfire, it slows down performance, run them as 2 separate cards

[mullick]

fixed

[pccs]

did you ever get it figured out?

Nope, not really. I have 2 rigs running now.

Rig #1:
2 Gigabyte 7970 - both cards are on powered risers running just over 700Khs. The thing I don't like is  they fluctuate between ~698 - ~712 constantly. If I move the mouse the hash rate on both cards drops way down to the 600s and then climbs back to the 700+ range. I'm not using a dummy plug on the second card.

Rig #2:
3 7970s - 2 Gigabyte and 1 XFX. 2 on powered risers. 1 card plugged into the MB. The GB cards run around 710Khs, XFX at 610Khs but all 3 cards fluctuate just like Rig #1. No dummy plugs here either.


Both systems have 16GB ram, one processor is an Athlon and the other a Sempron.

How stable should the hash rate be? Is it normal for the hash rate to jump around constantly? Hard to tell from just screen shots of other systems.

What I plan on trying one of these days is installing a 6450 that I have, setting that to the system card and then disabling it in CGMiner.

I got rid of the beta driver and am currently using the AMD 13.1 driver and CGMiner 3.1 and the SDK is 2.7

I am not using the Crossfire connector.

[pccs]

Is there a way to move this to the correct board?

Not sure how it got into the alt currencies thread.