Are you sure you have 1 bad drive. It is possible that an error occured on one of the drive but not necessarily a hardware failure. Such error can be cleared(after you read/understand the nature) on the RAID utilities/tools.
I had the same issue before but my controller is from Intel. It was a case of data-transfer type error that i had to clear.
Same as you have right now. The error was FLAG at BIOS Level(during start-up). I clear it using the RAID utilities/tools from Intel.