diff --git a/src/cpu.c b/src/cpu.c
index e381931..0c4487d 100644
--- a/src/cpu.c
+++ b/src/cpu.c
@@ -333,6 +333,7 @@ void cpu_set()
 
         timing_misaligned = 0;
         cpu_cyrix_alignment = 0;
+        cpu_CR4_mask = 0;
         
         switch (cpu_s->cpu_type)
         {