diff --git a/src/mainboard/aopen/dxplplusu/acpi/e7505_pri.asl b/src/mainboard/aopen/dxplplusu/acpi/e7505_pri.asl
index d258ec9d42..f8c7b2e23a 100644
--- a/src/mainboard/aopen/dxplplusu/acpi/e7505_pri.asl
+++ b/src/mainboard/aopen/dxplplusu/acpi/e7505_pri.asl
@@ -49,7 +49,7 @@ Device (MBRS)
 		CreateDWordField (MSBF, \_SB.MBRS._Y1D._LEN, MEM2)
 		And (\_SB.PCI0.TOLM, 0xF800, Local1)
 		ShiftRight (Local1, 0x04, Local1)
-		Decrement (Local1)
+		Local1--
 		If (LGreater (Local1, 0x10))
 		{
 			Local1 -= 0x0F