diff --git a/Source/Core/Core/ConfigManager.cpp b/Source/Core/Core/ConfigManager.cpp
index 8d0f8d2cb0..3272f7a3b4 100644
--- a/Source/Core/Core/ConfigManager.cpp
+++ b/Source/Core/Core/ConfigManager.cpp
@@ -499,11 +499,11 @@ void SConfig::LoadCoreSettings(IniFile& ini)
 
 	core->Get("HLE_BS2",      &m_LocalCoreStartupParameter.bHLE_BS2, false);
 #ifdef _M_X86
-	core->Get("CPUCore",      &m_LocalCoreStartupParameter.iCPUCore, 1);
+	core->Get("CPUCore",      &m_LocalCoreStartupParameter.iCPUCore, SCoreStartupParameter::CORE_JIT64);
 #elif _M_ARM_32
-	core->Get("CPUCore",      &m_LocalCoreStartupParameter.iCPUCore, 3);
+	core->Get("CPUCore",      &m_LocalCoreStartupParameter.iCPUCore, SCoreStartupParameter::CORE_JITARM);
 #else
-	core->Get("CPUCore",      &m_LocalCoreStartupParameter.iCPUCore, 0);
+	core->Get("CPUCore",      &m_LocalCoreStartupParameter.iCPUCore, SCoreStartupParameter::CORE_INTERPRETER);
 #endif
 	core->Get("Fastmem",           &m_LocalCoreStartupParameter.bFastmem,      true);
 	core->Get("DSPThread",         &m_LocalCoreStartupParameter.bDSPThread,    false);
diff --git a/Source/Core/Core/Core.cpp b/Source/Core/Core/Core.cpp
index 2b36fa6f3f..5d2ff0ab96 100644
--- a/Source/Core/Core/Core.cpp
+++ b/Source/Core/Core/Core.cpp
@@ -326,14 +326,14 @@ static void FifoPlayerThread()
 // See the BootManager.cpp file description for a complete call schedule.
 void EmuThread()
 {
-	const SCoreStartupParameter& _CoreParameter =
+	const SCoreStartupParameter& core_parameter =
 		SConfig::GetInstance().m_LocalCoreStartupParameter;
 
 	Common::SetCurrentThreadName("Emuthread - Starting");
 
 	DisplayMessage(cpu_info.brand_string, 8000);
 	DisplayMessage(cpu_info.Summarize(), 8000);
-	DisplayMessage(_CoreParameter.m_strFilename, 3000);
+	DisplayMessage(core_parameter.m_strFilename, 3000);
 
 	Movie::Init();
 
@@ -348,7 +348,7 @@ void EmuThread()
 
 	OSD::AddMessage("Dolphin " + g_video_backend->GetName() + " Video Backend.", 5000);
 
-	if (!DSP::GetDSPEmulator()->Initialize(_CoreParameter.bWii, _CoreParameter.bDSPThread))
+	if (!DSP::GetDSPEmulator()->Initialize(core_parameter.bWii, core_parameter.bDSPThread))
 	{
 		HW::Shutdown();
 		g_video_backend->Shutdown();
@@ -359,7 +359,7 @@ void EmuThread()
 
 	Pad::Initialize(s_window_handle);
 	// Load and Init Wiimotes - only if we are booting in wii mode
-	if (_CoreParameter.bWii)
+	if (core_parameter.bWii)
 	{
 		Wiimote::Initialize(s_window_handle, !s_state_filename.empty());
 
@@ -376,7 +376,7 @@ void EmuThread()
 	s_hardware_initialized = true;
 
 	// Boot to pause or not
-	Core::SetState(_CoreParameter.bBootToPause ? Core::CORE_PAUSE : Core::CORE_RUN);
+	Core::SetState(core_parameter.bBootToPause ? Core::CORE_PAUSE : Core::CORE_RUN);
 
 	// Load GCM/DOL/ELF whatever ... we boot with the interpreter core
 	PowerPC::SetMode(PowerPC::MODE_INTERPRETER);
@@ -384,11 +384,15 @@ void EmuThread()
 	CBoot::BootUp();
 
 	// Setup our core, but can't use dynarec if we are compare server
-	if (_CoreParameter.iCPUCore && (!_CoreParameter.bRunCompareServer ||
-					_CoreParameter.bRunCompareClient))
+	if (core_parameter.iCPUCore != SCoreStartupParameter::CORE_INTERPRETER
+	    && (!core_parameter.bRunCompareServer || core_parameter.bRunCompareClient))
+	{
 		PowerPC::SetMode(PowerPC::MODE_JIT);
+	}
 	else
+	{
 		PowerPC::SetMode(PowerPC::MODE_INTERPRETER);
+	}
 
 	// Update the window again because all stuff is initialized
 	Host_UpdateDisasmDialog();
@@ -396,13 +400,13 @@ void EmuThread()
 
 	// Determine the cpu thread function
 	void (*cpuThreadFunc)(void);
-	if (_CoreParameter.m_BootType == SCoreStartupParameter::BOOT_DFF)
+	if (core_parameter.m_BootType == SCoreStartupParameter::BOOT_DFF)
 		cpuThreadFunc = FifoPlayerThread;
 	else
 		cpuThreadFunc = CpuThread;
 
 	// ENTER THE VIDEO THREAD LOOP
-	if (_CoreParameter.bCPUThread)
+	if (core_parameter.bCPUThread)
 	{
 		// This thread, after creating the EmuWindow, spawns a CPU
 		// thread, and then takes over and becomes the video thread
@@ -453,7 +457,7 @@ void EmuThread()
 
 	INFO_LOG(CONSOLE, "%s", StopMessage(true, "CPU thread stopped.").c_str());
 
-	if (_CoreParameter.bCPUThread)
+	if (core_parameter.bCPUThread)
 		g_video_backend->Video_Cleanup();
 
 	VolumeHandler::EjectVolume();
@@ -479,7 +483,7 @@ void EmuThread()
 	g_video_backend->Video_ClearMessages();
 
 	// Reload sysconf file in order to see changes committed during emulation
-	if (_CoreParameter.bWii)
+	if (core_parameter.bWii)
 		SConfig::GetInstance().m_SYSCONF->Reload();
 
 	INFO_LOG(CONSOLE, "Stop [Video Thread]\t\t---- Shutdown complete ----");
diff --git a/Source/Core/Core/CoreParameter.cpp b/Source/Core/Core/CoreParameter.cpp
index 92055d9eff..ff5daa783c 100644
--- a/Source/Core/Core/CoreParameter.cpp
+++ b/Source/Core/Core/CoreParameter.cpp
@@ -65,7 +65,7 @@ void SCoreStartupParameter::LoadDefaults()
 	iGDBPort = -1;
 	#endif
 
-	iCPUCore = 1;
+	iCPUCore = CORE_JIT64;
 	bCPUThread = false;
 	bSkipIdle = false;
 	bRunCompareServer = false;
diff --git a/Source/Core/Core/CoreParameter.h b/Source/Core/Core/CoreParameter.h
index 77d6a43c32..bdf979e0dd 100644
--- a/Source/Core/Core/CoreParameter.h
+++ b/Source/Core/Core/CoreParameter.h
@@ -116,10 +116,14 @@ struct SCoreStartupParameter
 	bool bAutomaticStart;
 	bool bBootToPause;
 
-	// 0 = Interpreter
-	// 1 = Jit
-	// 2 = JitIL
-	// 3 = JIT ARM
+	enum
+	{
+		CORE_INTERPRETER,
+		CORE_JIT64,
+		CORE_JITIL64,
+		CORE_JITARM,
+		CORE_JITARM64
+	};
 	int iCPUCore;
 
 	// JIT (shared between JIT and JITIL)
diff --git a/Source/Core/DolphinWX/ConfigMain.cpp b/Source/Core/DolphinWX/ConfigMain.cpp
index ac68bd63dd..925803d2af 100644
--- a/Source/Core/DolphinWX/ConfigMain.cpp
+++ b/Source/Core/DolphinWX/ConfigMain.cpp
@@ -878,32 +878,36 @@ void CConfigMain::OnOk(wxCommandEvent& WXUNUSED (event))
 // Core settings
 void CConfigMain::CoreSettingsChanged(wxCommandEvent& event)
 {
+	SCoreStartupParameter& startup_params = SConfig::GetInstance().m_LocalCoreStartupParameter;
+
 	switch (event.GetId())
 	{
 	// Core - Basic
 	case ID_CPUTHREAD:
 		if (Core::IsRunning())
 			return;
-		SConfig::GetInstance().m_LocalCoreStartupParameter.bCPUThread = CPUThread->IsChecked();
+		startup_params.bCPUThread = CPUThread->IsChecked();
 		break;
 	case ID_IDLESKIP:
-		SConfig::GetInstance().m_LocalCoreStartupParameter.bSkipIdle = SkipIdle->IsChecked();
+		startup_params.bSkipIdle = SkipIdle->IsChecked();
 		break;
 	case ID_ENABLECHEATS:
-		SConfig::GetInstance().m_LocalCoreStartupParameter.bEnableCheats = EnableCheats->IsChecked();
+		startup_params.bEnableCheats = EnableCheats->IsChecked();
 		break;
 	case ID_FRAMELIMIT:
 		SConfig::GetInstance().m_Framelimit = Framelimit->GetSelection();
 		break;
 	// Core - Advanced
 	case ID_CPUENGINE:
-		SConfig::GetInstance().m_LocalCoreStartupParameter.iCPUCore = CPUCores[CPUEngine->GetSelection()].CPUid;
+		startup_params.iCPUCore = CPUCores[CPUEngine->GetSelection()].CPUid;
 		if (main_frame->g_pCodeWindow)
-			main_frame->g_pCodeWindow->GetMenuBar()->Check(IDM_INTERPRETER,
-				SConfig::GetInstance().m_LocalCoreStartupParameter.iCPUCore?false:true);
+		{
+			bool using_interp = (startup_params.iCPUCore == SCoreStartupParameter::CORE_INTERPRETER);
+			main_frame->g_pCodeWindow->GetMenuBar()->Check(IDM_INTERPRETER, using_interp);
+		}
 		break;
 	case ID_NTSCJ:
-		SConfig::GetInstance().m_LocalCoreStartupParameter.bForceNTSCJ = _NTSCJ->IsChecked();
+		startup_params.bForceNTSCJ = _NTSCJ->IsChecked();
 		break;
 	}
 }
diff --git a/Source/Core/DolphinWX/Debugger/CodeWindow.cpp b/Source/Core/DolphinWX/Debugger/CodeWindow.cpp
index 4af423e134..94ca897a7b 100644
--- a/Source/Core/DolphinWX/Debugger/CodeWindow.cpp
+++ b/Source/Core/DolphinWX/Debugger/CodeWindow.cpp
@@ -384,7 +384,7 @@ void CCodeWindow::UpdateCallstack()
 }
 
 // Create CPU Mode menus
-void CCodeWindow::CreateMenu(const SCoreStartupParameter& _LocalCoreStartupParameter, wxMenuBar *pMenuBar)
+void CCodeWindow::CreateMenu(const SCoreStartupParameter& core_startup_parameter, wxMenuBar *pMenuBar)
 {
 	// CPU Mode
 	wxMenu* pCoreMenu = new wxMenu;
@@ -394,7 +394,7 @@ void CCodeWindow::CreateMenu(const SCoreStartupParameter& _LocalCoreStartupParam
 		" and stepping to work as explained in the Developer Documentation. But it can be very"
 		" slow, perhaps slower than 1 fps."),
 		wxITEM_CHECK);
-	interpreter->Check(_LocalCoreStartupParameter.iCPUCore == 0);
+	interpreter->Check(core_startup_parameter.iCPUCore == SCoreStartupParameter::CORE_INTERPRETER);
 	pCoreMenu->AppendSeparator();
 
 	pCoreMenu->Append(IDM_JITNOBLOCKLINKING, _("&JIT Block Linking off"),