diff --git a/Source/Interface/Core/OpcodeDispatcher.cpp b/Source/Interface/Core/OpcodeDispatcher.cpp
index dfe9c9a9e..4549d2a3e 100644
--- a/Source/Interface/Core/OpcodeDispatcher.cpp
+++ b/Source/Interface/Core/OpcodeDispatcher.cpp
@@ -4107,6 +4107,14 @@ void OpDispatchBuilder::PAlignrOp(OpcodeArgs) {
   StoreResult(Op, Res, -1);
 }
 
+void OpDispatchBuilder::LDMXCSR(OpcodeArgs) {
+}
+
+void OpDispatchBuilder::STMXCSR(OpcodeArgs) {
+  // Default MXCSR
+  StoreResult(Op, _Constant(0x1F80), -1);
+}
+
 void OpDispatchBuilder::UnimplementedOp(OpcodeArgs) {
   // We don't actually support this instruction
   // Multiblock may hit it though
@@ -4536,8 +4544,11 @@ constexpr uint16_t PF_F2 = 3;
     // GROUP 15
     {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_NONE, 0), 1, &OpDispatchBuilder::FXSaveOp},
     {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_NONE, 1), 1, &OpDispatchBuilder::FXRStoreOp},
-    {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_NONE, 5), 1, &OpDispatchBuilder::UnimplementedOp},
-    {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_NONE, 7), 1, &OpDispatchBuilder::UnimplementedOp},
+    {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_NONE, 2), 1, &OpDispatchBuilder::LDMXCSR},
+    {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_NONE, 3), 1, &OpDispatchBuilder::STMXCSR},
+    {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_NONE, 5), 1, &OpDispatchBuilder::NOPOp}, //LFENCE
+    {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_NONE, 6), 1, &OpDispatchBuilder::NOPOp}, //MFENCE
+    {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_NONE, 7), 1, &OpDispatchBuilder::NOPOp}, //SFENCE
 
     {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_F3, 5), 1, &OpDispatchBuilder::UnimplementedOp},
     {OPD(FEXCore::X86Tables::TYPE_GROUP_15, PF_F3, 6), 1, &OpDispatchBuilder::UnimplementedOp},
diff --git a/Source/Interface/Core/OpcodeDispatcher.h b/Source/Interface/Core/OpcodeDispatcher.h
index 56cebca6c..381787808 100644
--- a/Source/Interface/Core/OpcodeDispatcher.h
+++ b/Source/Interface/Core/OpcodeDispatcher.h
@@ -225,6 +225,9 @@ public:
   void FXRStoreOp(OpcodeArgs);
 
   void PAlignrOp(OpcodeArgs);
+  void LDMXCSR(OpcodeArgs);
+  void STMXCSR(OpcodeArgs);
+
   void UnimplementedOp(OpcodeArgs);
 
 #undef OpcodeArgs