Can't seem to get all my cards work. Always after a bit of mining, one card goes to 0h/s which is annoying. I have 10 vegas, used to work perfectly on srb version 1.4.9 till i updated to 1.5.4. Now After some mining one card hangs, then it can't even be detected, whole pc also hangs, I am trying 9 cards now to see if I get same error. Also re-enabled the watchdog to see if that helps.
go back to 1.4.9 for a few days and test. I think it's more a windows-update-driver-who knows problem, than miner new version problem.