this morning I added my third card to my little rig and let it run with Dwarfpool a few hours.
There I get constant ~135 (+/-5) shares/hour. Since 3 1/2 hours I let the miner run with Ethpool.org.
Same local mining speed and config. But after this time I see 220 shares/ 0.0% invalid, that means only ~63 shares per hour!
Is this a bad joke or what? If this doesn´t raise, I better go back to Dwarfpool.