diff --git a/Makefile.power b/Makefile.power
index 5c431860f..b2fa04386 100644
--- a/Makefile.power
+++ b/Makefile.power
@@ -34,8 +34,11 @@ ifeq ($(USE_OPENMP), 1)
 COMMON_OPT += -Ofast -mcpu=power8 -mtune=power8 -mvsx -malign-power -DUSE_OPENMP -fno-fast-math -fopenmp
 FCOMMON_OPT += -O2 -frecursive -mcpu=power8 -mtune=power8 -malign-power -DUSE_OPENMP -fno-fast-math -fopenmp
 else
-COMMON_OPT += -Ofast -mcpu=power8 -mtune=power8 -mvsx -malign-power -fno-fast-math
-FCOMMON_OPT += -O2 -frecursive -mcpu=power8 -mtune=power8 -malign-power -fno-fast-math
+COMMON_OPT += -Ofast -mcpu=power8 -mtune=power8 -mvsx -malign-power -fno-fast-math 
+FCOMMON_OPT += -O2 -frecursive -mcpu=power8 -mtune=power8 -malign-power -fno-fast-math 
+ifeq ($(OSNAME), AIX)
+FCOMMON_OPT += -O1 -frecursive -mcpu=power8 -mtune=power8 -malign-power -fno-fast-math 
+endif
 endif
 endif
 
@@ -78,6 +81,9 @@ CCOMMON_OPT	+= -mpowerpc64 -maix64
 ifeq ($(COMPILER_F77), g77)
 FCOMMON_OPT	+= -mpowerpc64 -maix64
 endif
+ifeq ($(F_COMPILER), GFORTRAN)
+FCOMMON_OPT	+= -mpowerpc64 -maix64
+endif
 ifeq ($(COMPILER_F77), xlf)
 FCOMMON_OPT	+= -q64
 endif