Claymore,
I think, in the next update you should optimize and correct the "-a" function.
Now it is:
-a Select algorithm:
"-a 0" (default) means autoselection.
"-a 1" fastest mining mode for 290/290x and 270/270x cards.
"-a 2" low power consumption mode for 290/290x cards. A bit less speed (1%) but less power consumption (10-15%).
"-a 3" fastest mining for old cards (6xxx and 5xxx).
"-a 4" fastest mining for recent cards (280x, 270/270x etc).
In "-a 1" we have 270/270x, but in "-a 4" too?!
And the description in just a miner issue.
I have my RX470/4 recognised as RX470 from the miner. BUT - it auto selects mode "-a 1". And in order to prevent the pool from constantly saying "lowdifficultyshare" I had to underclock (!!!) them.
When mode is changed to "-a 4" - just occasional "red" messages about low diff.
On the other hand - another rig (This time with RX470/8) also autodetected on "-a 1" mode, but no problems with lowdiffshare. And no difference if -a 1 or -a 4......
So, I think it would be good if this auto mode selection could be optimised.