Today I launched Phoenix miner 4.1c in dual mode with blake2s on three R9 290. They recently gave about 23 mh/s on Ether in solo. Unlike the RX series, there is no support in AMD drivers for a large DAG size for old cards, so their speed, which was once 30-31 max, has seriously decreased. Got a fantastic speed in the miner window (45 mh/s). Blake2s showed 1300 mh/s, but there were no shares at all.
I was very pleased, but after checking on the pool (Ethermine) it turned out that these are only numbers in the miner's console. The real speed remained 22-23 mh/s as it was earlier.