diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index 7b56243..88f092b 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -409,8 +409,8 @@
 CPUARG =
 !endif
 !else
-# VC8/9 only allows specifying SSE architecture
-!if "$(CPUNR)" == "pentium4"
+# VC8/9/10 only allows specifying SSE architecture but only for 32bit
+!if "$(ASSEMBLY_ARCHITECTURE)" == "x86" && "$(CPUNR)" == "pentium4"
 CPUARG = /arch:SSE2
 !endif
 !endif