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Bitcoin => Mining => Topic started by: pandemic on August 09, 2011, 12:52:48 PM



Title: two 5830's, same mh/s different share count
Post by: pandemic on August 09, 2011, 12:52:48 PM
I've got two 5830's both overclocked to the same specs and both get about 305-307mh/s stable.

This morning, I woke up and saw that card A only had 1238 accepted shares while card B had 2311 accepted shares. I see both are chugging away at 307mh/s.

... What would cause this?


Title: Re: two 5830's, same mh/s different share count
Post by: sgravina on August 09, 2011, 03:44:26 PM
Luck.

Every share you find is just like winning a difficulty 1 block.  You are calculating hashes until you get one that is less than some number then you submit that share and it is credited to you by your pool.

Sometimes is takes longer or shorter to find a solution to your share.

Sam


Title: Re: two 5830's, same mh/s different share count
Post by: getcopy on August 09, 2011, 03:46:25 PM
Luck.

Every share you find is just like winning a difficulty 1 block.  You are calculating hashes until you get one that is less than some number then you submit that share and it is credited to you by your pool.

Sometimes is takes longer or shorter to find a solution to your share.

Sam

Agree. It's all about luck.


Title: Re: two 5830's, same mh/s different share count
Post by: PcChip on August 09, 2011, 04:09:38 PM
1200 vs 2300 is more than just luck, you would think they should be within 10% of each other.

I was noticing a similar phenomenon on my new dedicated am3-sempron with Crossfire'd 5770's, both set to 930/300/1.125v, both getting the same hashrate, but one had not only less shares but also more rejects.  Doesn't make much sense to me since it wasn't reporting any OpenCL errors...

Maybe you and I should both run cgminer and monitor the "HW:" column (keeps track of any Hardware Erorrs)


Title: Re: two 5830's, same mh/s different share count
Post by: lowlevel on August 09, 2011, 04:13:42 PM
I had something similar to this happening for a while... basically GPU0 was locking up on me and hanging because I had loaded firefox or something.
Now I wont' use the computer while its mining... or if I lock up GPU0, I just close that miner window, and re-start it.


Title: Re: two 5830's, same mh/s different share count
Post by: PcChip on August 09, 2011, 04:18:06 PM
That doesn't really sound like the same issue we're having.

But two suggestions for your problem:

1.) If it's a 6 series card, I hear you have to disable acceleration for flash/youtube videos or it will crash

2.) if you're using poclbm, set -f 30 or -f 60, if you're using phoenix, set AGGRESSION=4 FASTLOOP


Title: Re: two 5830's, same mh/s different share count
Post by: pandemic on August 10, 2011, 03:07:09 AM
it's not happened since. Now I've been overclocking my 5830 to find the breaking point. My newer 5830 is 958/300 whereas the older version is up to 1040/300 and getting 330mh/s.

I ran them both at 958/300 before and was getting very similar results. Last night was the first time where they varied so widely. I ran it again and it was much better.

Even now, one card is running 307mh/s and has 3400shares whereas the other card running at 330mh/s is at 3700 shares. Not too far off considering the hashing difference.


Title: Re: two 5830's, same mh/s different share count
Post by: jjiimm_64 on August 10, 2011, 03:20:14 AM

I had 2 of those new 5830's.   they suck, sent them back to newegg.  I've been mining ebay for 5870's :)


Title: Re: two 5830's, same mh/s different share count
Post by: pandemic on August 10, 2011, 05:13:55 AM

I had 2 of those new 5830's.   they suck, sent them back to newegg.  I've been mining ebay for 5870's :)


meh, even my new one can get 307mh/s which is pretty good considering the card cost $100.


Title: Re: two 5830's, same mh/s different share count
Post by: pandemic on August 10, 2011, 04:18:28 PM
It's happening again. My card running at 1040/300 is doing about 333mh/s yet only had 3 accepted whereas my 958/300 card is going at 307mh/s and had about 50. I just restarted my computer and ran AOCLBF again. They're currently neck and neck at 4 each. We'll see what happens in a few hours.


Title: Re: two 5830's, same mh/s different share count
Post by: CanaryInTheMine on August 14, 2011, 04:36:29 AM
sounds like it's crashing the miner.

run your mining from command prompt using verbose mode and you'll see what's up.

I recommend phoenix 1.5, it will output all info you need.

I do use aolblahblah for overcklocking only...


Title: Re: two 5830's, same mh/s different share count
Post by: kiwiasian on August 14, 2011, 08:23:55 PM
No, it's not luck. GPU2 for me is always 350 mh/s and accepts more sharess than my 370 mh/s miner. Why? I don't know. But does it matter? Probably not.


Title: Re: two 5830's, same mh/s different share count
Post by: sgravina on August 15, 2011, 12:22:50 AM
I was wrong about it being luck.  I didn't notice how huge a difference it was.

I had a problem with one of my cards and through much switching of components I realized that my power supply simply would not power a third card.  Whatever card attached to the third set of wires would run OK then slow, then stall, etc.  Today I bought a new supply and all the cards are working.

Sam


Title: Re: two 5830's, same mh/s different share count
Post by: satechheads on August 18, 2011, 07:13:04 AM
I have been satisfied with the 5830's I got from newegg. They were $109 and I am getting 330 Mhash from each of them consistently. OC to 1000 mhz on the core and 300 on the memory using phoenix and phatk with aggression=12 and worksize=256

http://techheadsblogs.com/images/rig1.png