Bitcoin Forum
December 18, 2017, 09:07:46 PM *
News: Latest stable version of Bitcoin Core: 0.15.1  [Torrent].
 
   Home   Help Search Donate Login Register  
Pages: [1]
  Print  
Author Topic: [SOLVED] 2x 7950s dropping to 64% load every few seconds  (Read 5835 times)
wazoo42
Jr. Member
*
Offline Offline

Activity: 42


View Profile
March 21, 2013, 04:55:07 AM
 #1

I am running these on gentoo with cgminer 2.11.3 (I've tried 2.10.4 as well), and I noticed that the MH/s for each card initially goes up to 505/526 for the first minute or two. Over the next 3-5 minutes it settles into 480/490 MH/s. In the first period the gpu load is 98-100%, but as it declines and once it hits steady state the gpu load alternates between 64% and 98-100%. I have tried altering the intensity (8, 9, 10), the worksize (256, 512, 1024), the # of gpu threads (1, 2, 3), and the queue size (1,3,5), and the kernel (diakgcn, diablo, poclbm). All of these settings give the same behavior (though the starting and steady state hashing speeds differ slightly). I do not see this behavior on my boxes with 2x5830s, 2x5770s, or 1x7950 & 1x5770. Any thoughts as to what might be causing this or some other test I can try?
1513631266
Hero Member
*
Offline Offline

Posts: 1513631266

View Profile Personal Message (Offline)

Ignore
1513631266
Reply with quote  #2

1513631266
Report to moderator
Advertised sites are not endorsed by the Bitcoin Forum. They may be unsafe, untrustworthy, or illegal in your jurisdiction. Advertise here.
DrG
Legendary
*
Offline Offline

Activity: 1624



View Profile
March 21, 2013, 09:36:07 AM
 #2

Two common causes that I have seen:
1) Thermal throttling.  Are the cards getting too hot?  If they're above 85C they might be throttling. When one of my 6870s went bad it did the same thing - throttled back at 106C lol
2) Something running amuck in the back of Windows (like some other program tying up resources too much).  If it's a linux rig I have no idea.  Best solution for windows is just do a clean install, not worth wasting time trying to diagnose the cause.

BTC: 1AMfUrM37cCHcAvyYGx9bsJWjt6rdCu7sj
ETH: 0x427f41c3a6b79ca643210195a33cdbaa714177aa
-ck
Staff
Legendary
*
Offline Offline

Activity: 2366


Ruu \o/


View Profile WWW
March 21, 2013, 09:38:05 AM
 #3

And not enough power.

Primary developer/maintainer for cgminer and ckpool/ckproxy.
ZERO FEE Pooled mining at ckpool.org 1% Fee Solo mining at solo.ckpool.org
-ck
wazoo42
Jr. Member
*
Offline Offline

Activity: 42


View Profile
March 21, 2013, 02:08:10 PM
 #4

The temps are 73/57 C and it is linux. They are fed by a 1000 W rosewill bronze psu. I may see if I can get my hands on a bigger one, though this model does have 4 pci connectors, so I thought it could handle it.
DrG
Legendary
*
Offline Offline

Activity: 1624



View Profile
March 22, 2013, 12:16:40 AM
 #5

Temps probably aren't the problem then.

Rosewill as a general rule makes crappy PSUs, but their Capstone series are pretty nice.  Does the PSU put out at least 60Amps on the 12V lines?

I'm not well versed on power since I'm not an engineer, but if you launch GPU-Z and look at the sensors you can see what the 12v drops down to while both are mining.  It could be the PSU is bad.

BTC: 1AMfUrM37cCHcAvyYGx9bsJWjt6rdCu7sj
ETH: 0x427f41c3a6b79ca643210195a33cdbaa714177aa
wazoo42
Jr. Member
*
Offline Offline

Activity: 42


View Profile
March 22, 2013, 04:05:00 AM
 #6

It has 4x12 V rails with 20, 20, 30, and 30 A on each rail. What they don't say is if they put 1 pci-e per rail. They also don't specify how the regular 12 V molex connectors are distributed across the rails. I will try putting one or two pci-e 6 pin adapters on these. Sadly the it87 sensor on this motherboard does not give me much useful voltage information. I suppose my next test would be to get a 500 W psu and use it to run one of the cards independently.
wazoo42
Jr. Member
*
Offline Offline

Activity: 42


View Profile
March 24, 2013, 06:39:51 PM
 #7

I ran one of the cards off of an antec 550W with 2x12 V rails w/ 19 A per rail. Thus, I really don't know if this tells me anything new b/c I'd run into the same problem if both connectors pulled off the same rail (for the record, both with this psu and the rosewill, I tried all combinations of pci-e and 4 pin molex + pci-e adapters). The kill-a-watt showed about 150 W before mining starts, and then 370 W with one card or 585 W with both cards. It would appear that 20 A probably isn't enough. Needless to say, the end result was the same as before. I will see if I can get my hands on a psu with larger 12 V rails.
glendall
Hero Member
*****
Offline Offline

Activity: 952


View Profile
April 02, 2013, 05:05:30 PM
 #8

Hey fellow new miner.

Think I got the answer for you. Just picked up a 7950 the other day and had same thing. GPU dropped to 66% every so often.

Go into the Catalyst Control Centre software/console.  Go to the AMD Overdrive setting.  There is a power setting option. This sets the power threshold. Increase this to the max, 20% .

Basically by default these cards power down / reduce the clock if running at 100% to save power and GPU life.

After increasing this to 20% I'm maintaining  99% gpu activity at high 70's temperature.
Vuxil
Newbie
*
Offline Offline

Activity: 28



View Profile
April 03, 2013, 05:58:07 AM
 #9

Hey fellow new miner.

Think I got the answer for you. Just picked up a 7950 the other day and had same thing. GPU dropped to 66% every so often.

Go into the Catalyst Control Centre software/console.  Go to the AMD Overdrive setting.  There is a power setting option. This sets the power threshold. Increase this to the max, 20% .

Basically by default these cards power down / reduce the clock if running at 100% to save power and GPU life.

After increasing this to 20% I'm maintaining  99% gpu activity at high 70's temperature.

Do you know if there is a config file that can be editted to change this? My *nix box is headless

PPCoin Mining Pool (North America) - www.VuxilsPool.com (http://www.VuxilsPool.com)          PPC: PQTkB3PNt9S3kdac8AbWeVFMqnTfnu3Gki
LTC: LPrtTHQAYT8RkmLtQpRwuRUxTRWEY4YA12           BTC: 16svR9TYqkP1VMoitxm6umgEXgAQHRe94H
wazoo42
Jr. Member
*
Offline Offline

Activity: 42


View Profile
April 03, 2013, 04:10:48 PM
 #10

The short answer is that ati control center no longer has overdrive capability and the power settings are controlled by libatiadlxx.so. You can create a program, powercontrol, to alter the power settings using (the export command is necessary for doing this remotely)

Code:
export DISPLAY=:0 ; ./powercontrol

https://bitcointalk.org/index.php?topic=7374.895;wap2
Sy
Legendary
*
Offline Offline

Activity: 952


World's First Reverse Merchant Processor


View Profile
December 06, 2013, 07:10:35 AM
 #11

Is this still the solution to go? Got the same problem with my 280x but the fix isn't working -.-

knapol96
Newbie
*
Offline Offline

Activity: 6



View Profile
January 27, 2014, 02:40:15 PM
 #12

me too, need to solve it but it still occurs after increasing the power by 20%

Donations : 1Lp6haxKZ2YwfUX5ZPPNPFBD85xosuTtnk

If you have to many BitCoins : 1Lp6haxKZ2YwfUX5ZPPNPFBD85xosuTtnk
Sy
Legendary
*
Offline Offline

Activity: 952


World's First Reverse Merchant Processor


View Profile
January 27, 2014, 06:33:33 PM
 #13

It was a cooling problem for me, Sapphire 280x Dual-X

Just downclocked themself if they came close to 80C

BillGeo
Newbie
*
Offline Offline

Activity: 25


View Profile
April 14, 2014, 12:55:46 PM
 #14

In my case it WAS poor cooling (i dont know what or how PowerTune +20 fixed).


I got a cooling fan failure (a big external one, not on the card itself) and VRAM temps skyrocketed to 110oC
so the card began to throttle so it won't burn up in smoke!


Go the fans working reliably again, all is good!!!
 Smiley

Get it on!!!
reactor
Sr. Member
****
Offline Offline

Activity: 406



View Profile
April 14, 2014, 03:16:43 PM
 #15

And not enough power.

90% of the time it is this or temperature. ^^^

The rest of the time hardware isn't getting along (system usage, memory speed and availability, rogue processes) or you're pushing the card too hard.  Back in my infancy when I used the GUI-heavy variant for mining I'd just put in settings I found on the wiki for cards and be baffled that I'd get system resets and the like.  Pay careful attention to stats from cgminer - just made a modification to frequency or voltage and have a high HW or R rate?  Tweak down and retry.  

If you have windows, try something like GPU Caps Viewer for monitoring temp/cycles.  If you have MSI, try using something like afterburner (may have name wrong, it's the MSI monitoring app) to see the usage graphs to trace the drops.  For example, one MSI card I had tweaked to the 9's but my cooling wasn't adequate so it'd throttle for temp and eventually crash the drivers.  Removed the plastic cover and did some aftermarket hack cooling and the card screams hashing now.  

Pages: [1]
  Print  
 
Jump to:  

Sponsored by , a Bitcoin-accepting VPN.
Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!