Be aggressive!!

[stryker]

Hmm seems I've made a newbie mistake.  I've got 3 GPUs and figured that as nothing uses the second 2 I never gave the aggression settings a second thought, had it set to 10.

Well, I tried cards 2 & 3 at aggression 12 and now my hashing rate has gone from drifting around 841-849 Mh/s to being pegged at 851 Mh/s

DOH!

Just thought I'd share, let this be a lesson 

[Dargo]

In my experience, you have to be careful with high aggression settings. High aggression settings do bump up the hash rate that is reported on your end by your mining software. But what pays is your share acceptance rate at the pool where you mine. And I've found for my 5850s that high aggression settings actually throttle my share acceptance rate. I played around with this when I had two 5850s, and I found that I got the optimal share acceptance rate with one card set at 7 aggression and the other at 9. Anything higher than this and my share acceptance rate started to go down rather than up. Perhaps you won't have the same result, but you should look into your share acceptance rate and make sure that higher hash rates on your end are in fact translating into higher share acceptance rates. Due to variance in luck, you have to let your rig run for a while at any setting to make sure that the change in acceptance rate isn't just due to luck, so it is tricky and time consuming to tune your cards this way. In fact, to screen out effects due to luck, you probably want to mine for a while at one setting, calculate your share acceptance rate, then change the setting, let the cards mine for a while, then change the settings back and let the cards mine for a while at the old setting. But I think you can get a rough feel for the acceptance rate while you are rough tuning without doing this. I now have four 5850s, and I have one set at 7 and the other 3 at 9, but I haven't had the time to tune all four for max share acceptance rate. Anyway, just tossing this out as something to consider. 

[haploid23]

hmm interesting. i assume you guys are only talking about phoenix based miners?

[Dargo]

Yes, but other miners have similar settings. In poclbm, for example, you have the "-f" flag which also sets kernel execution times. But I haven't tested this to see if there is a similar throttling of share submission rates at aggressive settings. I should try this at some point, since if there isn't, this would offer an advantage over phoenix. BTW, I do remember reading some posts by other members about 2 months ago who were noticing the same phenomenon I describe, so it doesn't seem to be limited just to me. 

[stryker]

Cheers for the comments, I'll certainly keep an eye on things.  Yes its phoenix.

Interesting thing I've noticed.... it was that all my 3 cards were at aggression 10.  gpu0 had a solid hashing rate while gpus 1&2 were the ones fluctuating.  However now gpu0 is agg 10 while 1 & 2 are now 12 and guess what? gpu0 is the one fluctuating and 1 & 2 are rock solid!!  As gpu0 is a 6770 and 1 & 2 are 6830's I think I'll leave things as they are for now.  FYI the 6770 used to crash on agg 12 but that was with linuxcoin where as I now use BAMT.

Sorry the graph is a little small but it does show what I'm talking about, you can see when I raised the aggression on 1 & 2.

[stryker]

oh very funny