I stopped mining this several days ago.  Since about update 1.5 i stopped finding blocks.  I could not get pool mining to work either.  Before this update I had a Cudaminer that could find blocks and so I pointed my 280x rig to it.  Both my rigs were running 100% boinc.  When I was finding blocks they were proper payout.  I attempted pool mining and got nothing as well.  I will try again soon.