It is critical that the scoreboard be able to distinguish RAW and WAR hazards, because a WAR hazard requires stalling the instruction doing the writing until the instruction reading an operand initiates execution, but a RAW hazard

Instruction producing result Instruction using result Latency in clock cycles FP multiply FP ALU op 6 FP add FP ALU op 4 FP multiply FP store 5 FP add FP store 3 Integer operation (including load) Any 0 requires delaying the reading instruction until the writing instruction finishes