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Other => Beginners & Help => Topic started by: VolK on June 29, 2012, 01:17:37 PM



Title: Crazy Fluxuations using HD6870
Post by: VolK on June 29, 2012, 01:17:37 PM
Hey all, I'm pretty new to mining, and I'd like some advice! I'm running a single XFX 6870 (In my gaming maching, may make a dedicated miner when I have the money). Coreclk is at 930, memclk is at 830, running guiminer with flags -v -w 128. For the first day or two I was using these settings, it worked fine, and i'd have a peek of maybe 270 Mhash/s and about 96% GPU usage consistently. As of last night my mhash rate was going crazy, jumping anywhere from 250mh/s to 120 mh/s, peeking at a max of 70% GPU usage for a few seconds then dropping and going back up again. I have no idea what the problem is, and checking my average mh/s on my BTCGUILD account tells me I'm only getting about 134-150 mh/s a second, even with my monitor off and nothing running. These crazy fluctuations happen even at stock clocks and with no flags.


Title: Re: Crazy Fluxuations using HD6870
Post by: Blaztoize on June 29, 2012, 01:22:47 PM
First I'd like to welcome you to the community! :)

How are temperatures looking on the GPU? Sounds like it could be going through periods of underclocking itself due to heat. I leave fans at 100% and forget about 'em. I know you said it's at stock, but try this out? Sorry if this isn't the case. Perhaps someone else can chime in.

But the average being reported at your pool isn't going to be extremely consistent, though they would like it to seem that way. It will fluctuate up and down depending on your good/bad luck.


Title: Re: Crazy Fluxuations using HD6870
Post by: VolK on June 29, 2012, 01:28:24 PM
How are temperatures looking on the GPU? Sounds like it could be going through periods of underclocking itself due to heat. I leave fans at 100% and forget about 'em. Sorry if this isn't the case. Perhaps someone else can chime in.

But the average being reported at your pool isn't going to be extremely consistent, though they would like it to seem that way, in it's reportings as compared to your miner. It will fluctuate up and down depending on your good/bad luck.

I have my fan set to 70% and its staying at about 66 degrees C. I also have a case fan pulling cold air straight into my GPU, and my case has pretty good airflow. I'm also in a room that stays about... 65 Fahrenheit constantly in the summer, so I don't think that temperature is the problem.


Title: Re: Crazy Fluxuations using HD6870
Post by: Blaztoize on June 29, 2012, 01:36:07 PM
Have you changed any drivers in the past few days? Catalyst and SDKs sometimes don't play nice.

I know this isn't necessarily an end-all solution, but if you just really want to start mining with the power you have, try another program. I used to experience similar fluctuations with DiabloMiner. I ended up switching to cgminer, getting better hash rates, more reporting consistency, and haven't looked back since.

Apologies I can't be more helpful.


Title: Re: Crazy Fluxuations using HD6870
Post by: VolK on June 29, 2012, 01:39:22 PM
Have you changed any drivers in the past few days? Catalyst and SDKs sometimes don't play nice.

I know this isn't necessarily an end-all solution, but if you just really want to start mining with the power you have, try another program. I used to experience similar fluctuations with DiabloMiner. I ended up switching to cgminer, getting better hash rates, more reporting consistency, and haven't looked back since.

Apologies I can't be more helpful.

I don't know, but I don't think so, but I just checked my rate on GUIminer, and its back to about 240-250 mh/s.... Must have been some odd bug or something, because the problem seems to have fixed itself