diff --git a/Source/Android/jni/MainAndroid.cpp b/Source/Android/jni/MainAndroid.cpp
index 730175e340..69f76bfe3d 100644
--- a/Source/Android/jni/MainAndroid.cpp
+++ b/Source/Android/jni/MainAndroid.cpp
@@ -445,7 +445,7 @@ JNIEXPORT jstring JNICALL Java_org_dolphinemu_dolphinemu_NativeLibrary_GetUserDi
 JNIEXPORT jint JNICALL Java_org_dolphinemu_dolphinemu_NativeLibrary_DefaultCPUCore(JNIEnv* env,
                                                                                    jobject obj)
 {
-  return PowerPC::DefaultCPUCore();
+  return static_cast<jint>(PowerPC::DefaultCPUCore());
 }
 
 JNIEXPORT void JNICALL Java_org_dolphinemu_dolphinemu_NativeLibrary_SetProfiling(JNIEnv* env,
diff --git a/Source/Core/Common/StringUtil.h b/Source/Core/Common/StringUtil.h
index 11c873bdae..0ee2391e7c 100644
--- a/Source/Core/Common/StringUtil.h
+++ b/Source/Core/Common/StringUtil.h
@@ -55,14 +55,14 @@ static bool TryParse(const std::string& str, N* const output)
   // separators
   iss.imbue(std::locale("C"));
 
-  N tmp = 0;
+  N tmp;
   if (iss >> tmp)
   {
     *output = tmp;
     return true;
   }
-  else
-    return false;
+
+  return false;
 }
 
 template <typename N>
diff --git a/Source/Core/Core/BootManager.cpp b/Source/Core/Core/BootManager.cpp
index 9d524f7df3..6040b2824f 100644
--- a/Source/Core/Core/BootManager.cpp
+++ b/Source/Core/Core/BootManager.cpp
@@ -28,16 +28,12 @@
 #include "Common/FileUtil.h"
 #include "Common/IniFile.h"
 #include "Common/Logging/Log.h"
-#include "Common/MsgHandler.h"
 #include "Common/StringUtil.h"
 
-#include "Common/Config/Config.h"
 #include "Core/Boot/Boot.h"
 #include "Core/Config/MainSettings.h"
 #include "Core/Config/SYSCONFSettings.h"
 #include "Core/ConfigLoaders/BaseConfigLoader.h"
-#include "Core/ConfigLoaders/GameConfigLoader.h"
-#include "Core/ConfigLoaders/MovieConfigLoader.h"
 #include "Core/ConfigLoaders/NetPlayConfigLoader.h"
 #include "Core/ConfigManager.h"
 #include "Core/Core.h"
@@ -47,6 +43,7 @@
 #include "Core/HW/WiimoteReal/WiimoteReal.h"
 #include "Core/Movie.h"
 #include "Core/NetPlayProto.h"
+#include "Core/PowerPC/PowerPC.h"
 
 #include "DiscIO/Enums.h"
 
@@ -88,7 +85,7 @@ private:
   bool bDSPHLE;
   bool bHLE_BS2;
   int iSelectedLanguage;
-  int iCPUCore;
+  PowerPC::CPUCore cpu_core;
   int Volume;
   float m_EmulationSpeed;
   float m_OCFactor;
@@ -118,7 +115,7 @@ void ConfigCache::SaveConfig(const SConfig& config)
   bDSPHLE = config.bDSPHLE;
   bHLE_BS2 = config.bHLE_BS2;
   iSelectedLanguage = config.SelectedLanguage;
-  iCPUCore = config.iCPUCore;
+  cpu_core = config.cpu_core;
   Volume = config.m_Volume;
   m_EmulationSpeed = config.m_EmulationSpeed;
   strBackend = config.m_strVideoBackend;
@@ -159,7 +156,7 @@ void ConfigCache::RestoreConfig(SConfig* config)
   config->bDSPHLE = bDSPHLE;
   config->bHLE_BS2 = bHLE_BS2;
   config->SelectedLanguage = iSelectedLanguage;
-  config->iCPUCore = iCPUCore;
+  config->cpu_core = cpu_core;
 
   // Only change these back if they were actually set by game ini, since they can be changed while a
   // game is running.
@@ -255,7 +252,7 @@ bool BootCore(std::unique_ptr<BootParameters> boot)
     core_section->Get("FastDiscSpeed", &StartUp.bFastDiscSpeed, StartUp.bFastDiscSpeed);
     core_section->Get("DSPHLE", &StartUp.bDSPHLE, StartUp.bDSPHLE);
     core_section->Get("GFXBackend", &StartUp.m_strVideoBackend, StartUp.m_strVideoBackend);
-    core_section->Get("CPUCore", &StartUp.iCPUCore, StartUp.iCPUCore);
+    core_section->Get("CPUCore", &StartUp.cpu_core, StartUp.cpu_core);
     core_section->Get("HLE_BS2", &StartUp.bHLE_BS2, StartUp.bHLE_BS2);
     core_section->Get("GameCubeLanguage", &StartUp.SelectedLanguage, StartUp.SelectedLanguage);
     if (core_section->Get("EmulationSpeed", &StartUp.m_EmulationSpeed, StartUp.m_EmulationSpeed))
@@ -317,7 +314,7 @@ bool BootCore(std::unique_ptr<BootParameters> boot)
     StartUp.bCPUThread = Config::Get(Config::MAIN_CPU_THREAD);
     StartUp.bDSPHLE = Config::Get(Config::MAIN_DSP_HLE);
     StartUp.bFastDiscSpeed = Config::Get(Config::MAIN_FAST_DISC_SPEED);
-    StartUp.iCPUCore = Config::Get(Config::MAIN_CPU_CORE);
+    StartUp.cpu_core = Config::Get(Config::MAIN_CPU_CORE);
     StartUp.bSyncGPU = Config::Get(Config::MAIN_SYNC_GPU);
     if (!StartUp.bWii)
       StartUp.SelectedLanguage = Config::Get(Config::MAIN_GC_LANGUAGE);
@@ -343,7 +340,7 @@ bool BootCore(std::unique_ptr<BootParameters> boot)
     StartUp.bDSPHLE = g_NetPlaySettings.m_DSPHLE;
     StartUp.bEnableMemcardSdWriting = g_NetPlaySettings.m_WriteToMemcard;
     StartUp.bCopyWiiSaveNetplay = g_NetPlaySettings.m_CopyWiiSave;
-    StartUp.iCPUCore = g_NetPlaySettings.m_CPUcore;
+    StartUp.cpu_core = g_NetPlaySettings.m_CPUcore;
     StartUp.SelectedLanguage = g_NetPlaySettings.m_SelectedLanguage;
     StartUp.bOverrideGCLanguage = g_NetPlaySettings.m_OverrideGCLanguage;
     StartUp.m_DSPEnableJIT = g_NetPlaySettings.m_DSPEnableJIT;
diff --git a/Source/Core/Core/Config/MainSettings.cpp b/Source/Core/Core/Config/MainSettings.cpp
index 9f4811bdb3..1b9d01a9dc 100644
--- a/Source/Core/Core/Config/MainSettings.cpp
+++ b/Source/Core/Core/Config/MainSettings.cpp
@@ -16,7 +16,8 @@ namespace Config
 // Main.Core
 
 const ConfigInfo<bool> MAIN_SKIP_IPL{{System::Main, "Core", "SkipIPL"}, true};
-const ConfigInfo<int> MAIN_CPU_CORE{{System::Main, "Core", "CPUCore"}, PowerPC::DefaultCPUCore()};
+const ConfigInfo<PowerPC::CPUCore> MAIN_CPU_CORE{{System::Main, "Core", "CPUCore"},
+                                                 PowerPC::DefaultCPUCore()};
 const ConfigInfo<bool> MAIN_FASTMEM{{System::Main, "Core", "Fastmem"}, true};
 const ConfigInfo<bool> MAIN_DSP_HLE{{System::Main, "Core", "DSPHLE"}, true};
 const ConfigInfo<int> MAIN_TIMING_VARIANCE{{System::Main, "Core", "TimingVariance"}, 40};
diff --git a/Source/Core/Core/Config/MainSettings.h b/Source/Core/Core/Config/MainSettings.h
index ab99f889d7..2277e27cab 100644
--- a/Source/Core/Core/Config/MainSettings.h
+++ b/Source/Core/Core/Config/MainSettings.h
@@ -8,12 +8,17 @@
 
 #include "Common/Config/Config.h"
 
+namespace PowerPC
+{
+enum class CPUCore;
+}
+
 namespace Config
 {
 // Main.Core
 
 extern const ConfigInfo<bool> MAIN_SKIP_IPL;
-extern const ConfigInfo<int> MAIN_CPU_CORE;
+extern const ConfigInfo<PowerPC::CPUCore> MAIN_CPU_CORE;
 extern const ConfigInfo<bool> MAIN_FASTMEM;
 // Should really be in the DSP section, but we're kind of stuck with bad decisions made in the past.
 extern const ConfigInfo<bool> MAIN_DSP_HLE;
diff --git a/Source/Core/Core/ConfigLoaders/MovieConfigLoader.cpp b/Source/Core/Core/ConfigLoaders/MovieConfigLoader.cpp
index 86ce99b8da..fb8378bbdf 100644
--- a/Source/Core/Core/ConfigLoaders/MovieConfigLoader.cpp
+++ b/Source/Core/Core/ConfigLoaders/MovieConfigLoader.cpp
@@ -8,10 +8,8 @@
 #include <memory>
 #include <string>
 
-#include "Common/CommonFuncs.h"
 #include "Common/CommonTypes.h"
 #include "Common/Config/Config.h"
-#include "Common/FileUtil.h"
 
 #include "Core/Config/GraphicsSettings.h"
 #include "Core/Config/MainSettings.h"
@@ -20,6 +18,11 @@
 #include "Core/Movie.h"
 #include "VideoCommon/VideoConfig.h"
 
+namespace PowerPC
+{
+enum class CPUCore;
+}
+
 namespace ConfigLoaders
 {
 static void LoadFromDTM(Config::Layer* config_layer, Movie::DTMHeader* dtm)
@@ -27,7 +30,7 @@ static void LoadFromDTM(Config::Layer* config_layer, Movie::DTMHeader* dtm)
   config_layer->Set(Config::MAIN_CPU_THREAD, dtm->bDualCore);
   config_layer->Set(Config::MAIN_DSP_HLE, dtm->bDSPHLE);
   config_layer->Set(Config::MAIN_FAST_DISC_SPEED, dtm->bFastDiscSpeed);
-  config_layer->Set(Config::MAIN_CPU_CORE, static_cast<int>(dtm->CPUCore));
+  config_layer->Set(Config::MAIN_CPU_CORE, static_cast<PowerPC::CPUCore>(dtm->CPUCore));
   config_layer->Set(Config::MAIN_SYNC_GPU, dtm->bSyncGPU);
   config_layer->Set(Config::MAIN_GFX_BACKEND, dtm->videoBackend.data());
 
@@ -50,7 +53,7 @@ void SaveToDTM(Movie::DTMHeader* dtm)
   dtm->bDualCore = Config::Get(Config::MAIN_CPU_THREAD);
   dtm->bDSPHLE = Config::Get(Config::MAIN_DSP_HLE);
   dtm->bFastDiscSpeed = Config::Get(Config::MAIN_FAST_DISC_SPEED);
-  dtm->CPUCore = Config::Get(Config::MAIN_CPU_CORE);
+  dtm->CPUCore = static_cast<u8>(Config::Get(Config::MAIN_CPU_CORE));
   dtm->bSyncGPU = Config::Get(Config::MAIN_SYNC_GPU);
   const std::string video_backend = Config::Get(Config::MAIN_GFX_BACKEND);
 
diff --git a/Source/Core/Core/ConfigManager.cpp b/Source/Core/Core/ConfigManager.cpp
index 9ccd12c9d9..f7656411ed 100644
--- a/Source/Core/Core/ConfigManager.cpp
+++ b/Source/Core/Core/ConfigManager.cpp
@@ -218,7 +218,7 @@ void SConfig::SaveCoreSettings(IniFile& ini)
 
   core->Set("SkipIPL", bHLE_BS2);
   core->Set("TimingVariance", iTimingVariance);
-  core->Set("CPUCore", iCPUCore);
+  core->Set("CPUCore", cpu_core);
   core->Set("Fastmem", bFastmem);
   core->Set("CPUThread", bCPUThread);
   core->Set("DSPHLE", bDSPHLE);
@@ -505,11 +505,11 @@ void SConfig::LoadCoreSettings(IniFile& ini)
 
   core->Get("SkipIPL", &bHLE_BS2, true);
 #ifdef _M_X86
-  core->Get("CPUCore", &iCPUCore, PowerPC::CORE_JIT64);
+  core->Get("CPUCore", &cpu_core, PowerPC::CPUCore::JIT64);
 #elif _M_ARM_64
-  core->Get("CPUCore", &iCPUCore, PowerPC::CORE_JITARM64);
+  core->Get("CPUCore", &cpu_core, PowerPC::CPUCore::JITARM64);
 #else
-  core->Get("CPUCore", &iCPUCore, PowerPC::CORE_INTERPRETER);
+  core->Get("CPUCore", &cpu_core, PowerPC::CPUCore::Interpreter);
 #endif
   core->Get("Fastmem", &bFastmem, true);
   core->Get("DSPHLE", &bDSPHLE, true);
@@ -763,7 +763,7 @@ void SConfig::LoadDefaults()
 #endif
 #endif
 
-  iCPUCore = PowerPC::DefaultCPUCore();
+  cpu_core = PowerPC::DefaultCPUCore();
   iTimingVariance = 40;
   bCPUThread = false;
   bSyncGPUOnSkipIdleHack = true;
diff --git a/Source/Core/Core/ConfigManager.h b/Source/Core/Core/ConfigManager.h
index 8c2ae27461..a01fc64c09 100644
--- a/Source/Core/Core/ConfigManager.h
+++ b/Source/Core/Core/ConfigManager.h
@@ -23,6 +23,7 @@ enum class Region;
 struct Partition;
 class Volume;
 }  // namespace DiscIO
+
 namespace IOS
 {
 namespace ES
@@ -31,6 +32,11 @@ class TMDReader;
 }
 }  // namespace IOS
 
+namespace PowerPC
+{
+enum class CPUCore;
+}  // namespace PowerPC
+
 // DSP Backend Types
 #define BACKEND_NULLSOUND _trans("No Audio Output")
 #define BACKEND_ALSA "ALSA"
@@ -75,7 +81,7 @@ struct SConfig
   bool bAutomaticStart = false;
   bool bBootToPause = false;
 
-  int iCPUCore;  // Uses the values of PowerPC::CPUCore
+  PowerPC::CPUCore cpu_core;
 
   bool bJITNoBlockCache = false;
   bool bJITNoBlockLinking = false;
diff --git a/Source/Core/Core/Core.cpp b/Source/Core/Core/Core.cpp
index 9d3c89dd52..f54e477be3 100644
--- a/Source/Core/Core/Core.cpp
+++ b/Source/Core/Core/Core.cpp
@@ -530,7 +530,7 @@ static void EmuThread(std::unique_ptr<BootParameters> boot)
   Fifo::Prepare();
 
   // Setup our core, but can't use dynarec if we are compare server
-  if (core_parameter.iCPUCore != PowerPC::CORE_INTERPRETER &&
+  if (core_parameter.cpu_core != PowerPC::CPUCore::Interpreter &&
       (!core_parameter.bRunCompareServer || core_parameter.bRunCompareClient))
   {
     PowerPC::SetMode(PowerPC::CoreMode::JIT);
diff --git a/Source/Core/Core/HW/CPU.cpp b/Source/Core/Core/HW/CPU.cpp
index b836a9ad7e..97ad890c29 100644
--- a/Source/Core/Core/HW/CPU.cpp
+++ b/Source/Core/Core/HW/CPU.cpp
@@ -45,7 +45,7 @@ static bool s_state_system_request_stepping = false;
 static bool s_state_cpu_step_instruction = false;
 static Common::Event* s_state_cpu_step_instruction_sync = nullptr;
 
-void Init(int cpu_core)
+void Init(PowerPC::CPUCore cpu_core)
 {
   PowerPC::Init(cpu_core);
   s_state = State::Stepping;
diff --git a/Source/Core/Core/HW/CPU.h b/Source/Core/Core/HW/CPU.h
index 5337483e3e..9f50afd611 100644
--- a/Source/Core/Core/HW/CPU.h
+++ b/Source/Core/Core/HW/CPU.h
@@ -9,6 +9,11 @@ namespace Common
 class Event;
 }
 
+namespace PowerPC
+{
+enum class CPUCore;
+}
+
 namespace CPU
 {
 enum class State
@@ -19,7 +24,7 @@ enum class State
 };
 
 // Init
-void Init(int cpu_core);
+void Init(PowerPC::CPUCore cpu_core);
 
 // Shutdown
 void Shutdown();
diff --git a/Source/Core/Core/HW/HW.cpp b/Source/Core/Core/HW/HW.cpp
index 5cf808ee3f..4e1732792f 100644
--- a/Source/Core/Core/HW/HW.cpp
+++ b/Source/Core/Core/HW/HW.cpp
@@ -45,7 +45,7 @@ void Init()
   DSP::Init(SConfig::GetInstance().bDSPHLE);
   DVDInterface::Init();
   GPFifo::Init();
-  CPU::Init(SConfig::GetInstance().iCPUCore);
+  CPU::Init(SConfig::GetInstance().cpu_core);
   SystemTimers::Init();
 
   if (SConfig::GetInstance().bWii)
diff --git a/Source/Core/Core/NetPlayClient.cpp b/Source/Core/Core/NetPlayClient.cpp
index 2533c001e4..6b2c226f88 100644
--- a/Source/Core/Core/NetPlayClient.cpp
+++ b/Source/Core/Core/NetPlayClient.cpp
@@ -12,6 +12,7 @@
 #include <mutex>
 #include <sstream>
 #include <thread>
+#include <type_traits>
 
 #include <mbedtls/md5.h>
 
@@ -35,6 +36,7 @@
 #include "Core/HW/WiimoteReal/WiimoteReal.h"
 #include "Core/IOS/USB/Bluetooth/BTEmu.h"
 #include "Core/Movie.h"
+#include "Core/PowerPC/PowerPC.h"
 #include "InputCommon/GCAdapter.h"
 #include "VideoCommon/OnScreenDisplay.h"
 #include "VideoCommon/VideoConfig.h"
@@ -412,7 +414,15 @@ unsigned int NetPlayClient::OnData(sf::Packet& packet)
       std::lock_guard<std::recursive_mutex> lkg(m_crit.game);
       packet >> m_current_game;
       packet >> g_NetPlaySettings.m_CPUthread;
-      packet >> g_NetPlaySettings.m_CPUcore;
+
+      {
+        std::underlying_type_t<PowerPC::CPUCore> core;
+        if (packet >> core)
+          g_NetPlaySettings.m_CPUcore = static_cast<PowerPC::CPUCore>(core);
+        else
+          g_NetPlaySettings.m_CPUcore = PowerPC::CPUCore::CachedInterpreter;
+      }
+
       packet >> g_NetPlaySettings.m_EnableCheats;
       packet >> g_NetPlaySettings.m_SelectedLanguage;
       packet >> g_NetPlaySettings.m_OverrideGCLanguage;
diff --git a/Source/Core/Core/NetPlayProto.h b/Source/Core/Core/NetPlayProto.h
index 3172c7a1c8..582c285d3c 100644
--- a/Source/Core/Core/NetPlayProto.h
+++ b/Source/Core/Core/NetPlayProto.h
@@ -9,10 +9,15 @@
 #include "Common/CommonTypes.h"
 #include "Core/HW/EXI/EXI_Device.h"
 
+namespace PowerPC
+{
+enum class CPUCore;
+}
+
 struct NetSettings
 {
   bool m_CPUthread;
-  int m_CPUcore;
+  PowerPC::CPUCore m_CPUcore;
   bool m_EnableCheats;
   int m_SelectedLanguage;
   bool m_OverrideGCLanguage;
diff --git a/Source/Core/Core/NetPlayServer.cpp b/Source/Core/Core/NetPlayServer.cpp
index 2ff168cc0d..416b358449 100644
--- a/Source/Core/Core/NetPlayServer.cpp
+++ b/Source/Core/Core/NetPlayServer.cpp
@@ -11,6 +11,7 @@
 #include <mutex>
 #include <string>
 #include <thread>
+#include <type_traits>
 #include <unordered_set>
 #include <vector>
 
@@ -815,10 +816,10 @@ bool NetPlayServer::StartGame()
 
   // tell clients to start game
   sf::Packet spac;
-  spac << (MessageId)NP_MSG_START_GAME;
+  spac << static_cast<MessageId>(NP_MSG_START_GAME);
   spac << m_current_game;
   spac << m_settings.m_CPUthread;
-  spac << m_settings.m_CPUcore;
+  spac << static_cast<std::underlying_type_t<PowerPC::CPUCore>>(m_settings.m_CPUcore);
   spac << m_settings.m_EnableCheats;
   spac << m_settings.m_SelectedLanguage;
   spac << m_settings.m_OverrideGCLanguage;
@@ -832,8 +833,8 @@ bool NetPlayServer::StartGame()
   spac << m_settings.m_OCFactor;
   spac << m_settings.m_EXIDevice[0];
   spac << m_settings.m_EXIDevice[1];
-  spac << (u32)g_netplay_initial_rtc;
-  spac << (u32)(g_netplay_initial_rtc >> 32);
+  spac << static_cast<u32>(g_netplay_initial_rtc);
+  spac << static_cast<u32>(g_netplay_initial_rtc >> 32);
 
   SendAsyncToClients(std::move(spac));
 
diff --git a/Source/Core/Core/PowerPC/JitInterface.cpp b/Source/Core/Core/PowerPC/JitInterface.cpp
index d2fac3eaab..7ca7ebaeb5 100644
--- a/Source/Core/Core/PowerPC/JitInterface.cpp
+++ b/Source/Core/Core/PowerPC/JitInterface.cpp
@@ -45,28 +45,28 @@ void DoState(PointerWrap& p)
   if (g_jit && p.GetMode() == PointerWrap::MODE_READ)
     g_jit->ClearCache();
 }
-CPUCoreBase* InitJitCore(int core)
+CPUCoreBase* InitJitCore(PowerPC::CPUCore core)
 {
   switch (core)
   {
 #if _M_X86
-  case PowerPC::CORE_JIT64:
+  case PowerPC::CPUCore::JIT64:
     g_jit = new Jit64();
     break;
 #endif
 #if _M_ARM_64
-  case PowerPC::CORE_JITARM64:
+  case PowerPC::CPUCore::JITARM64:
     g_jit = new JitArm64();
     break;
 #endif
-  case PowerPC::CORE_CACHEDINTERPRETER:
+  case PowerPC::CPUCore::CachedInterpreter:
     g_jit = new CachedInterpreter();
     break;
 
   default:
     PanicAlertT("The selected CPU emulation core (%d) is not available. "
                 "Please select a different CPU emulation core in the settings.",
-                core);
+                static_cast<int>(core));
     g_jit = nullptr;
     return nullptr;
   }
diff --git a/Source/Core/Core/PowerPC/JitInterface.h b/Source/Core/Core/PowerPC/JitInterface.h
index 2f6167b438..913e34148a 100644
--- a/Source/Core/Core/PowerPC/JitInterface.h
+++ b/Source/Core/Core/PowerPC/JitInterface.h
@@ -12,6 +12,11 @@
 class CPUCoreBase;
 class PointerWrap;
 
+namespace PowerPC
+{
+enum class CPUCore;
+}
+
 namespace Profiler
 {
 struct ProfileStats;
@@ -28,7 +33,7 @@ enum class ExceptionType
 
 void DoState(PointerWrap& p);
 
-CPUCoreBase* InitJitCore(int core);
+CPUCoreBase* InitJitCore(PowerPC::CPUCore core);
 CPUCoreBase* GetCore();
 
 // Debugging
diff --git a/Source/Core/Core/PowerPC/PowerPC.cpp b/Source/Core/Core/PowerPC/PowerPC.cpp
index 5ec07db2b3..0d44dc2cce 100644
--- a/Source/Core/Core/PowerPC/PowerPC.cpp
+++ b/Source/Core/Core/PowerPC/PowerPC.cpp
@@ -5,6 +5,9 @@
 #include "Core/PowerPC/PowerPC.h"
 
 #include <cstring>
+#include <istream>
+#include <ostream>
+#include <type_traits>
 #include <vector>
 
 #include "Common/Assert.h"
@@ -44,6 +47,30 @@ static void InvalidateCacheThreadSafe(u64 userdata, s64 cyclesLate)
   ppcState.iCache.Invalidate(static_cast<u32>(userdata));
 }
 
+std::istream& operator>>(std::istream& is, CPUCore& core)
+{
+  std::underlying_type_t<CPUCore> val{};
+
+  if (is >> val)
+  {
+    core = static_cast<CPUCore>(val);
+  }
+  else
+  {
+    // Upon failure, fall back to the cached interpreter
+    // to ensure we always initialize our core reference.
+    core = CPUCore::CachedInterpreter;
+  }
+
+  return is;
+}
+
+std::ostream& operator<<(std::ostream& os, CPUCore core)
+{
+  os << static_cast<std::underlying_type_t<CPUCore>>(core);
+  return os;
+}
+
 u32 CompactCR()
 {
   u32 new_cr = 0;
@@ -148,7 +175,7 @@ static void ResetRegisters()
   SystemTimers::DecrementerSet();
 }
 
-static void InitializeCPUCore(int cpu_core)
+static void InitializeCPUCore(CPUCore cpu_core)
 {
   // We initialize the interpreter because
   // it is used on boot and code window independently.
@@ -156,7 +183,7 @@ static void InitializeCPUCore(int cpu_core)
 
   switch (cpu_core)
   {
-  case PowerPC::CORE_INTERPRETER:
+  case CPUCore::Interpreter:
     s_cpu_core_base = s_interpreter;
     break;
 
@@ -176,12 +203,12 @@ static void InitializeCPUCore(int cpu_core)
 const std::vector<CPUCore>& AvailableCPUCores()
 {
   static const std::vector<CPUCore> cpu_cores = {
-      CORE_INTERPRETER,
-      CORE_CACHEDINTERPRETER,
+      CPUCore::Interpreter,
+      CPUCore::CachedInterpreter,
 #ifdef _M_X86_64
-      CORE_JIT64,
+      CPUCore::JIT64,
 #elif defined(_M_ARM_64)
-      CORE_JITARM64,
+      CPUCore::JITARM64,
 #endif
   };
 
@@ -191,15 +218,15 @@ const std::vector<CPUCore>& AvailableCPUCores()
 CPUCore DefaultCPUCore()
 {
 #ifdef _M_X86_64
-  return CORE_JIT64;
+  return CPUCore::JIT64;
 #elif defined(_M_ARM_64)
-  return CORE_JITARM64;
+  return CPUCore::JITARM64;
 #else
-  return CORE_CACHEDINTERPRETER;
+  return CPUCore::CachedInterpreter;
 #endif
 }
 
-void Init(int cpu_core)
+void Init(CPUCore cpu_core)
 {
   // NOTE: This function runs on EmuThread, not the CPU Thread.
   //   Changing the rounding mode has a limited effect.
diff --git a/Source/Core/Core/PowerPC/PowerPC.h b/Source/Core/Core/PowerPC/PowerPC.h
index de07134207..c6871dccd3 100644
--- a/Source/Core/Core/PowerPC/PowerPC.h
+++ b/Source/Core/Core/PowerPC/PowerPC.h
@@ -6,6 +6,7 @@
 
 #include <array>
 #include <cstddef>
+#include <iosfwd>
 #include <tuple>
 #include <vector>
 
@@ -23,14 +24,18 @@ namespace PowerPC
 {
 // The gaps in the CPUCore numbering are from cores that only existed in the past.
 // We avoid re-numbering cores so that settings will be compatible across versions.
-enum CPUCore
+enum class CPUCore
 {
-  CORE_INTERPRETER = 0,
-  CORE_JIT64 = 1,
-  CORE_JITARM64 = 4,
-  CORE_CACHEDINTERPRETER = 5,
+  Interpreter = 0,
+  JIT64 = 1,
+  JITARM64 = 4,
+  CachedInterpreter = 5,
 };
 
+// For reading from and writing to our config.
+std::istream& operator>>(std::istream& is, CPUCore& core);
+std::ostream& operator<<(std::ostream& os, CPUCore core);
+
 enum class CoreMode
 {
   Interpreter,
@@ -142,7 +147,7 @@ extern PPCDebugInterface debug_interface;
 const std::vector<CPUCore>& AvailableCPUCores();
 CPUCore DefaultCPUCore();
 
-void Init(int cpu_core);
+void Init(CPUCore cpu_core);
 void Reset();
 void Shutdown();
 void DoState(PointerWrap& p);
diff --git a/Source/Core/DolphinQt2/MenuBar.cpp b/Source/Core/DolphinQt2/MenuBar.cpp
index f7f4c047b0..712e3de39f 100644
--- a/Source/Core/DolphinQt2/MenuBar.cpp
+++ b/Source/Core/DolphinQt2/MenuBar.cpp
@@ -725,7 +725,8 @@ void MenuBar::AddJITMenu()
 
   m_jit_interpreter_core = m_jit->addAction(tr("Interpreter Core"));
   m_jit_interpreter_core->setCheckable(true);
-  m_jit_interpreter_core->setChecked(SConfig::GetInstance().iCPUCore == PowerPC::CORE_INTERPRETER);
+  m_jit_interpreter_core->setChecked(SConfig::GetInstance().cpu_core ==
+                                     PowerPC::CPUCore::Interpreter);
 
   connect(m_jit_interpreter_core, &QAction::toggled, [](bool enabled) {
     PowerPC::SetMode(enabled ? PowerPC::CoreMode::Interpreter : PowerPC::CoreMode::JIT);
diff --git a/Source/Core/DolphinQt2/NetPlay/NetPlayDialog.cpp b/Source/Core/DolphinQt2/NetPlay/NetPlayDialog.cpp
index 2e521be234..693e9c77d4 100644
--- a/Source/Core/DolphinQt2/NetPlay/NetPlayDialog.cpp
+++ b/Source/Core/DolphinQt2/NetPlay/NetPlayDialog.cpp
@@ -278,7 +278,7 @@ void NetPlayDialog::OnStart()
   // Copy all relevant settings
   SConfig& instance = SConfig::GetInstance();
   settings.m_CPUthread = instance.bCPUThread;
-  settings.m_CPUcore = instance.iCPUCore;
+  settings.m_CPUcore = instance.cpu_core;
   settings.m_EnableCheats = instance.bEnableCheats;
   settings.m_SelectedLanguage = instance.SelectedLanguage;
   settings.m_OverrideGCLanguage = instance.bOverrideGCLanguage;
diff --git a/Source/Core/DolphinQt2/Settings/GeneralPane.cpp b/Source/Core/DolphinQt2/Settings/GeneralPane.cpp
index 979e257a99..5384233569 100644
--- a/Source/Core/DolphinQt2/Settings/GeneralPane.cpp
+++ b/Source/Core/DolphinQt2/Settings/GeneralPane.cpp
@@ -38,10 +38,10 @@ constexpr const char* AUTO_UPDATE_BETA_STRING = "beta";
 constexpr const char* AUTO_UPDATE_DEV_STRING = "dev";
 
 static const std::map<PowerPC::CPUCore, const char*> CPU_CORE_NAMES = {
-    {PowerPC::CORE_INTERPRETER, QT_TR_NOOP("Interpreter (slowest)")},
-    {PowerPC::CORE_CACHEDINTERPRETER, QT_TR_NOOP("Cached Interpreter (slower)")},
-    {PowerPC::CORE_JIT64, QT_TR_NOOP("JIT Recompiler (recommended)")},
-    {PowerPC::CORE_JITARM64, QT_TR_NOOP("JIT Arm64 (experimental)")},
+    {PowerPC::CPUCore::Interpreter, QT_TR_NOOP("Interpreter (slowest)")},
+    {PowerPC::CPUCore::CachedInterpreter, QT_TR_NOOP("Cached Interpreter (slower)")},
+    {PowerPC::CPUCore::JIT64, QT_TR_NOOP("JIT Recompiler (recommended)")},
+    {PowerPC::CPUCore::JITARM64, QT_TR_NOOP("JIT Arm64 (experimental)")},
 };
 
 GeneralPane::GeneralPane(QWidget* parent) : QWidget(parent)
@@ -227,7 +227,7 @@ void GeneralPane::LoadConfig()
   const std::vector<PowerPC::CPUCore>& available_cpu_cores = PowerPC::AvailableCPUCores();
   for (size_t i = 0; i < available_cpu_cores.size(); ++i)
   {
-    if (available_cpu_cores[i] == SConfig::GetInstance().iCPUCore)
+    if (available_cpu_cores[i] == SConfig::GetInstance().cpu_core)
       m_cpu_cores[i]->setChecked(true);
   }
 }
@@ -275,7 +275,7 @@ void GeneralPane::OnSaveConfig()
   {
     if (m_cpu_cores[i]->isChecked())
     {
-      settings.iCPUCore = PowerPC::AvailableCPUCores()[i];
+      settings.cpu_core = PowerPC::AvailableCPUCores()[i];
       break;
     }
   }
diff --git a/Source/Core/DolphinWX/Config/GeneralConfigPane.cpp b/Source/Core/DolphinWX/Config/GeneralConfigPane.cpp
index 9083d514ac..da3f97f88f 100644
--- a/Source/Core/DolphinWX/Config/GeneralConfigPane.cpp
+++ b/Source/Core/DolphinWX/Config/GeneralConfigPane.cpp
@@ -26,10 +26,10 @@
 #include "DolphinWX/WxEventUtils.h"
 
 static const std::map<PowerPC::CPUCore, std::string> CPU_CORE_NAMES = {
-    {PowerPC::CORE_INTERPRETER, _trans("Interpreter (slowest)")},
-    {PowerPC::CORE_CACHEDINTERPRETER, _trans("Cached Interpreter (slower)")},
-    {PowerPC::CORE_JIT64, _trans("JIT Recompiler (recommended)")},
-    {PowerPC::CORE_JITARM64, _trans("JIT Arm64 (experimental)")},
+    {PowerPC::CPUCore::Interpreter, _trans("Interpreter (slowest)")},
+    {PowerPC::CPUCore::CachedInterpreter, _trans("Cached Interpreter (slower)")},
+    {PowerPC::CPUCore::JIT64, _trans("JIT Recompiler (recommended)")},
+    {PowerPC::CPUCore::JITARM64, _trans("JIT Arm64 (experimental)")},
 };
 
 GeneralConfigPane::GeneralConfigPane(wxWindow* parent, wxWindowID id) : wxPanel(parent, id)
@@ -156,7 +156,7 @@ void GeneralConfigPane::LoadGUIValues()
   const std::vector<PowerPC::CPUCore>& cpu_cores = PowerPC::AvailableCPUCores();
   for (size_t i = 0; i < cpu_cores.size(); ++i)
   {
-    if (cpu_cores[i] == startup_params.iCPUCore)
+    if (cpu_cores[i] == startup_params.cpu_core)
       m_cpu_engine_radiobox->SetSelection(i);
   }
 }
@@ -202,7 +202,7 @@ void GeneralConfigPane::OnThrottlerChoiceChanged(wxCommandEvent& event)
 
 void GeneralConfigPane::OnCPUEngineRadioBoxChanged(wxCommandEvent& event)
 {
-  SConfig::GetInstance().iCPUCore = PowerPC::AvailableCPUCores()[event.GetSelection()];
+  SConfig::GetInstance().cpu_core = PowerPC::AvailableCPUCores()[event.GetSelection()];
 }
 
 void GeneralConfigPane::OnAnalyticsCheckBoxChanged(wxCommandEvent& event)
diff --git a/Source/Core/DolphinWX/FrameTools.cpp b/Source/Core/DolphinWX/FrameTools.cpp
index d6d53af3a4..dfd4d487a0 100644
--- a/Source/Core/DolphinWX/FrameTools.cpp
+++ b/Source/Core/DolphinWX/FrameTools.cpp
@@ -1137,7 +1137,7 @@ void CFrame::OnUpdateInterpreterMenuItem(wxUpdateUIEvent& event)
   if (GetMenuBar()->FindItem(IDM_INTERPRETER)->IsChecked())
     return;
 
-  event.Check(SConfig::GetInstance().iCPUCore == PowerPC::CORE_INTERPRETER);
+  event.Check(SConfig::GetInstance().cpu_core == PowerPC::CPUCore::Interpreter);
 }
 
 void CFrame::ClearStatusBar()
diff --git a/Source/Core/DolphinWX/MainMenuBar.cpp b/Source/Core/DolphinWX/MainMenuBar.cpp
index 92c979ec62..ceed31516d 100644
--- a/Source/Core/DolphinWX/MainMenuBar.cpp
+++ b/Source/Core/DolphinWX/MainMenuBar.cpp
@@ -371,7 +371,7 @@ wxMenu* MainMenuBar::CreateJITMenu() const
       _("This is necessary to get break points"
         " and stepping to work as explained in the Developer Documentation. But it can be very"
         " slow, perhaps slower than 1 fps."));
-  interpreter->Check(config_instance.iCPUCore == PowerPC::CORE_INTERPRETER);
+  interpreter->Check(config_instance.cpu_core == PowerPC::CPUCore::Interpreter);
 
   jit_menu->AppendSeparator();
   jit_menu->AppendCheckItem(IDM_JIT_NO_BLOCK_LINKING, _("&JIT Block Linking Off"),
diff --git a/Source/Core/DolphinWX/NetPlay/NetWindow.cpp b/Source/Core/DolphinWX/NetPlay/NetWindow.cpp
index 1ece3e1bc1..de2e6d19f7 100644
--- a/Source/Core/DolphinWX/NetPlay/NetWindow.cpp
+++ b/Source/Core/DolphinWX/NetPlay/NetWindow.cpp
@@ -315,7 +315,7 @@ void NetPlayDialog::GetNetSettings(NetSettings& settings)
 {
   SConfig& instance = SConfig::GetInstance();
   settings.m_CPUthread = instance.bCPUThread;
-  settings.m_CPUcore = instance.iCPUCore;
+  settings.m_CPUcore = instance.cpu_core;
   settings.m_EnableCheats = instance.bEnableCheats;
   settings.m_SelectedLanguage = instance.SelectedLanguage;
   settings.m_OverrideGCLanguage = instance.bOverrideGCLanguage;
diff --git a/Source/UnitTests/Core/CoreTimingTest.cpp b/Source/UnitTests/Core/CoreTimingTest.cpp
index 2723c90d2a..8834a0262b 100644
--- a/Source/UnitTests/Core/CoreTimingTest.cpp
+++ b/Source/UnitTests/Core/CoreTimingTest.cpp
@@ -43,7 +43,7 @@ public:
     UICommon::SetUserDirectory(m_profile_path);
     Config::Init();
     SConfig::Init();
-    PowerPC::Init(PowerPC::CORE_INTERPRETER);
+    PowerPC::Init(PowerPC::CPUCore::Interpreter);
     CoreTiming::Init();
   }
   ~ScopeInit()