diff --git a/src/cpu/core_full/string.h b/src/cpu/core_full/string.h
index 0af58c1b..5da65b10 100644
--- a/src/cpu/core_full/string.h
+++ b/src/cpu/core_full/string.h
@@ -31,6 +31,7 @@
 			LoadIP();
 		} else {
 			/* Won't interrupt scas and cmps instruction since they can interrupt themselves */
+			if (inst.code.op<R_SCASB) CPU_Cycles-=count;
 			count_left=0;
 		}
 	}
diff --git a/src/cpu/core_normal/string.h b/src/cpu/core_normal/string.h
index a2639eb4..855397ad 100644
--- a/src/cpu/core_normal/string.h
+++ b/src/cpu/core_normal/string.h
@@ -34,8 +34,9 @@ static void DoString(STRING_OP type) {
 			CPU_Cycles=0;
 			LOADIP;		//RESET IP to the start
 		} else {
-			if ((count<=1) && (CPU_Cycles<=1)) CPU_Cycles--;
 			/* Won't interrupt scas and cmps instruction since they can interrupt themselves */
+			if ((count<=1) && (CPU_Cycles<=1)) CPU_Cycles--;
+			else if (type<R_SCASB) CPU_Cycles-=count;
 			count_left=0;
 		}
 	}