diff --git a/Makefile.system b/Makefile.system
index 4d7eb1610..79fb41569 100644
--- a/Makefile.system
+++ b/Makefile.system
@@ -46,12 +46,50 @@ ifdef TARGET
 GETARCH_FLAGS := -DFORCE_$(TARGET)
 endif
 
+# Force fallbacks for 32bit
+
+ifeq ($(BINARY), 32)
+ifeq ($(TARGET), HASWELL)
+GETARCH_FLAGS := -DFORCE_NEHALEM
+endif
+ifeq ($(TARGET), SANDYBRIDGE)
+GETARCH_FLAGS := -DFORCE_NEHALEM
+endif
+ifeq ($(TARGET), BULLDOZER)
+GETARCH_FLAGS := -DFORCE_BARCELONA
+endif
+ifeq ($(TARGET), PILEDRIVER)
+GETARCH_FLAGS := -DFORCE_BARCELONA
+endif
+endif
+
+
 #TARGET_CORE will override TARGET which is used in DYNAMIC_ARCH=1.
 #
 ifdef TARGET_CORE
 GETARCH_FLAGS := -DFORCE_$(TARGET_CORE)
 endif
 
+# Force fallbacks for 32bit
+
+ifeq ($(BINARY), 32)
+ifeq ($(TARGET_CORE), HASWELL)
+GETARCH_FLAGS := -DFORCE_NEHALEM
+endif
+ifeq ($(TARGET_CORE), SANDYBRIDGE)
+GETARCH_FLAGS := -DFORCE_NEHALEM
+endif
+ifeq ($(TARGET_CORE), BULLDOZER)
+GETARCH_FLAGS := -DFORCE_BARCELONA
+endif
+ifeq ($(TARGET_CORE), PILEDRIVER)
+GETARCH_FLAGS := -DFORCE_BARCELONA
+endif
+endif
+
+
+
+
 ifdef INTERFACE64
 ifneq ($(INTERFACE64), 0)
 GETARCH_FLAGS	+= -DUSE64BITINT
@@ -65,6 +103,9 @@ GETARCH_FLAGS	+= -DGEMM_MULTITHREAD_THRESHOLD=$(GEMM_MULTITHREAD_THRESHOLD)
 
 ifeq ($(NO_AVX), 1)
 GETARCH_FLAGS	+= -DNO_AVX
+ifeq ($(BINARY), 32)
+GETARCH_FLAGS	+= -DNO_AVX
+endif
 endif
 
 ifeq ($(DEBUG), 1)
@@ -338,9 +379,6 @@ ifeq ($(DYNAMIC_ARCH), 1)
 ifeq ($(ARCH), x86)
 DYNAMIC_CORE = KATMAI COPPERMINE NORTHWOOD PRESCOTT BANIAS \
 	       CORE2 PENRYN DUNNINGTON NEHALEM ATHLON OPTERON OPTERON_SSE3 BARCELONA BOBCAT ATOM NANO
-ifneq ($(NO_AVX), 1)
-DYNAMIC_CORE += SANDYBRIDGE BULLDOZER PILEDRIVER HASWELL
-endif
 endif
 
 ifeq ($(ARCH), x86_64)
@@ -732,7 +770,12 @@ endif
 
 ifeq ($(NO_AVX), 1)
 CCOMMON_OPT	+= -DNO_AVX
+else
+ifeq ($(BINARY), 32)
+CCOMMON_OPT	+= -DNO_AVX
 endif
+endif
+
 
 ifdef SMP
 CCOMMON_OPT	+= -DSMP_SERVER