diff --git a/Source/Core/DolphinQt/CMakeLists.txt b/Source/Core/DolphinQt/CMakeLists.txt
index 7990a5d32b..2cb3397e33 100644
--- a/Source/Core/DolphinQt/CMakeLists.txt
+++ b/Source/Core/DolphinQt/CMakeLists.txt
@@ -77,6 +77,8 @@ add_executable(dolphin-emu
   Config/FreeLookWidget.h
   Config/FreeLookWindow.cpp
   Config/FreeLookWindow.h
+  Config/GamecubeControllersWidget.cpp
+  Config/GamecubeControllersWidget.h
   Config/GameConfigEdit.cpp
   Config/GameConfigEdit.h
   Config/GameConfigHighlighter.cpp
diff --git a/Source/Core/DolphinQt/Config/ControllersWindow.cpp b/Source/Core/DolphinQt/Config/ControllersWindow.cpp
index f368ac9a72..1a4edce284 100644
--- a/Source/Core/DolphinQt/Config/ControllersWindow.cpp
+++ b/Source/Core/DolphinQt/Config/ControllersWindow.cpp
@@ -4,107 +4,32 @@
 
 #include "DolphinQt/Config/ControllersWindow.h"
 
-#include <QApplication>
-#include <QBoxLayout>
-#include <QCheckBox>
-#include <QComboBox>
-#include <QDialog>
 #include <QDialogButtonBox>
-#include <QGridLayout>
-#include <QGroupBox>
-#include <QLabel>
-#include <QLineEdit>
-#include <QPushButton>
-#include <QRadioButton>
-#include <QScreen>
 #include <QVBoxLayout>
 
-#include <map>
-#include <optional>
-
-#include "Core/ConfigManager.h"
-#include "Core/Core.h"
-#include "Core/HW/SI/SI.h"
-#include "Core/HW/SI/SI_Device.h"
-#include "Core/IOS/IOS.h"
-
 #include "DolphinQt/Config/CommonControllersWidget.h"
-#include "DolphinQt/Config/Mapping/GCPadWiiUConfigDialog.h"
-#include "DolphinQt/Config/Mapping/MappingWindow.h"
+#include "DolphinQt/Config/GamecubeControllersWidget.h"
 #include "DolphinQt/Config/WiimoteControllersWidget.h"
 #include "DolphinQt/QtUtils/WrapInScrollArea.h"
-#include "DolphinQt/Settings.h"
-
-#include "InputCommon/GCAdapter.h"
-
-#include "UICommon/UICommon.h"
-
-static const std::map<SerialInterface::SIDevices, int> s_gc_types = {
-    {SerialInterface::SIDEVICE_NONE, 0},         {SerialInterface::SIDEVICE_GC_CONTROLLER, 1},
-    {SerialInterface::SIDEVICE_WIIU_ADAPTER, 2}, {SerialInterface::SIDEVICE_GC_STEERING, 3},
-    {SerialInterface::SIDEVICE_DANCEMAT, 4},     {SerialInterface::SIDEVICE_GC_TARUKONGA, 5},
-    {SerialInterface::SIDEVICE_GC_GBA, 6},       {SerialInterface::SIDEVICE_GC_KEYBOARD, 7}};
-
-static std::optional<int> ToGCMenuIndex(const SerialInterface::SIDevices sidevice)
-{
-  auto it = s_gc_types.find(sidevice);
-  return it != s_gc_types.end() ? it->second : std::optional<int>();
-}
-
-static std::optional<SerialInterface::SIDevices> FromGCMenuIndex(const int menudevice)
-{
-  auto it = std::find_if(s_gc_types.begin(), s_gc_types.end(),
-                         [=](auto pair) { return pair.second == menudevice; });
-  return it != s_gc_types.end() ? it->first : std::optional<SerialInterface::SIDevices>();
-}
 
 ControllersWindow::ControllersWindow(QWidget* parent) : QDialog(parent)
 {
   setWindowTitle(tr("Controller Settings"));
   setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
 
-  CreateGamecubeLayout();
+  m_gamecube_controllers = new GamecubeControllersWidget(this);
   m_wiimote_controllers = new WiimoteControllersWidget(this);
   m_common = new CommonControllersWidget(this);
   CreateMainLayout();
-  LoadSettings();
   ConnectWidgets();
 }
 
-void ControllersWindow::CreateGamecubeLayout()
-{
-  m_gc_box = new QGroupBox(tr("GameCube Controllers"));
-  m_gc_layout = new QGridLayout();
-  m_gc_layout->setVerticalSpacing(7);
-  m_gc_layout->setColumnStretch(1, 1);
-
-  for (size_t i = 0; i < m_gc_groups.size(); i++)
-  {
-    auto* gc_label = new QLabel(tr("Port %1").arg(i + 1));
-    auto* gc_box = m_gc_controller_boxes[i] = new QComboBox();
-    auto* gc_button = m_gc_buttons[i] = new QPushButton(tr("Configure"));
-
-    for (const auto& item :
-         {tr("None"), tr("Standard Controller"), tr("GameCube Adapter for Wii U"),
-          tr("Steering Wheel"), tr("Dance Mat"), tr("DK Bongos"), tr("GBA"), tr("Keyboard")})
-    {
-      gc_box->addItem(item);
-    }
-
-    int controller_row = m_gc_layout->rowCount();
-    m_gc_layout->addWidget(gc_label, controller_row, 0);
-    m_gc_layout->addWidget(gc_box, controller_row, 1);
-    m_gc_layout->addWidget(gc_button, controller_row, 2);
-  }
-  m_gc_box->setLayout(m_gc_layout);
-}
-
 void ControllersWindow::CreateMainLayout()
 {
   auto* layout = new QVBoxLayout();
   m_button_box = new QDialogButtonBox(QDialogButtonBox::Close);
 
-  layout->addWidget(m_gc_box);
+  layout->addWidget(m_gamecube_controllers);
   layout->addWidget(m_wiimote_controllers);
   layout->addWidget(m_common);
   layout->addStretch();
@@ -116,112 +41,4 @@ void ControllersWindow::CreateMainLayout()
 void ControllersWindow::ConnectWidgets()
 {
   connect(m_button_box, &QDialogButtonBox::rejected, this, &QDialog::reject);
-
-  for (size_t i = 0; i < m_gc_groups.size(); i++)
-  {
-    connect(m_gc_controller_boxes[i], qOverload<int>(&QComboBox::currentIndexChanged), this,
-            &ControllersWindow::SaveSettings);
-    connect(m_gc_controller_boxes[i], qOverload<int>(&QComboBox::currentIndexChanged), this,
-            &ControllersWindow::OnGCTypeChanged);
-    connect(m_gc_buttons[i], &QPushButton::clicked, this, &ControllersWindow::OnGCPadConfigure);
-  }
-}
-
-void ControllersWindow::OnGCTypeChanged(int type)
-{
-  const auto* box = static_cast<QComboBox*>(QObject::sender());
-
-  for (size_t i = 0; i < m_gc_groups.size(); i++)
-  {
-    if (m_gc_controller_boxes[i] == box)
-    {
-      const int index = box->currentIndex();
-      m_gc_buttons[i]->setEnabled(index != 0 && index != 6);
-      return;
-    }
-  }
-
-  SaveSettings();
-}
-
-void ControllersWindow::OnGCPadConfigure()
-{
-  size_t index;
-  for (index = 0; index < m_gc_groups.size(); index++)
-  {
-    if (m_gc_buttons[index] == QObject::sender())
-      break;
-  }
-
-  MappingWindow::Type type;
-
-  switch (m_gc_controller_boxes[index]->currentIndex())
-  {
-  case 0:  // None
-  case 6:  // GBA
-    return;
-  case 1:  // Standard Controller
-    type = MappingWindow::Type::MAPPING_GCPAD;
-    break;
-  case 2:  // GameCube Adapter for Wii U
-    GCPadWiiUConfigDialog(static_cast<int>(index), this).exec();
-    return;
-  case 3:  // Steering Wheel
-    type = MappingWindow::Type::MAPPING_GC_STEERINGWHEEL;
-    break;
-  case 4:  // Dance Mat
-    type = MappingWindow::Type::MAPPING_GC_DANCEMAT;
-    break;
-  case 5:  // DK Bongos
-    type = MappingWindow::Type::MAPPING_GC_BONGOS;
-    break;
-  case 7:  // Keyboard
-    type = MappingWindow::Type::MAPPING_GC_KEYBOARD;
-    break;
-  default:
-    return;
-  }
-
-  MappingWindow* window = new MappingWindow(this, type, static_cast<int>(index));
-  window->setAttribute(Qt::WA_DeleteOnClose, true);
-  window->setWindowModality(Qt::WindowModality::WindowModal);
-  window->show();
-}
-
-void ControllersWindow::LoadSettings()
-{
-  for (size_t i = 0; i < m_gc_groups.size(); i++)
-  {
-    const std::optional<int> gc_index = ToGCMenuIndex(SConfig::GetInstance().m_SIDevice[i]);
-    if (gc_index)
-    {
-      m_gc_controller_boxes[i]->setCurrentIndex(*gc_index);
-      m_gc_buttons[i]->setEnabled(*gc_index != 0 && *gc_index != 6);
-    }
-  }
-}
-
-void ControllersWindow::SaveSettings()
-{
-  for (size_t i = 0; i < m_gc_groups.size(); i++)
-  {
-    const int index = m_gc_controller_boxes[i]->currentIndex();
-    const std::optional<SerialInterface::SIDevices> si_device = FromGCMenuIndex(index);
-    if (si_device)
-    {
-      SConfig::GetInstance().m_SIDevice[i] = *si_device;
-
-      if (Core::IsRunning())
-        SerialInterface::ChangeDevice(*si_device, static_cast<s32>(i));
-    }
-
-    m_gc_buttons[i]->setEnabled(index != 0 && index != 6);
-  }
-
-  if (GCAdapter::UseAdapter())
-    GCAdapter::StartScanThread();
-  else
-    GCAdapter::StopScanThread();
-
-  SConfig::GetInstance().SaveSettings();
 }
diff --git a/Source/Core/DolphinQt/Config/ControllersWindow.h b/Source/Core/DolphinQt/Config/ControllersWindow.h
index 13a4d8d73d..608f677720 100644
--- a/Source/Core/DolphinQt/Config/ControllersWindow.h
+++ b/Source/Core/DolphinQt/Config/ControllersWindow.h
@@ -6,19 +6,9 @@
 
 #include <QDialog>
 
-#include <array>
-
 class CommonControllersWidget;
-class MappingWindow;
+class GamecubeControllersWidget;
 class QDialogButtonBox;
-class QCheckBox;
-class QComboBox;
-class QHBoxLayout;
-class QGridLayout;
-class QGroupBox;
-class QLabel;
-class QPushButton;
-class QRadioButton;
 class WiimoteControllersWidget;
 
 class ControllersWindow final : public QDialog
@@ -28,28 +18,11 @@ public:
   explicit ControllersWindow(QWidget* parent);
 
 private:
-  void OnGCTypeChanged(int state);
-  void SaveSettings();
-  void OnGCPadConfigure();
-
-  void CreateGamecubeLayout();
   void CreateMainLayout();
   void ConnectWidgets();
-  void LoadSettings();
 
-  // Main
   QDialogButtonBox* m_button_box;
-
-  // Gamecube
-  QGroupBox* m_gc_box;
-  QGridLayout* m_gc_layout;
-  std::array<QComboBox*, 4> m_gc_controller_boxes;
-  std::array<QPushButton*, 4> m_gc_buttons;
-  std::array<QHBoxLayout*, 4> m_gc_groups;
-
-  // Wii Remote
+  GamecubeControllersWidget* m_gamecube_controllers;
   WiimoteControllersWidget* m_wiimote_controllers;
-
-  // Common
   CommonControllersWidget* m_common;
 };
diff --git a/Source/Core/DolphinQt/Config/GamecubeControllersWidget.cpp b/Source/Core/DolphinQt/Config/GamecubeControllersWidget.cpp
new file mode 100644
index 0000000000..205cbdaf03
--- /dev/null
+++ b/Source/Core/DolphinQt/Config/GamecubeControllersWidget.cpp
@@ -0,0 +1,198 @@
+// Copyright 2021 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include "DolphinQt/Config/GamecubeControllersWidget.h"
+
+#include <QComboBox>
+#include <QGridLayout>
+#include <QGroupBox>
+#include <QLabel>
+#include <QPushButton>
+#include <QVBoxLayout>
+
+#include <map>
+#include <optional>
+
+#include "Core/ConfigManager.h"
+#include "Core/Core.h"
+#include "Core/HW/SI/SI.h"
+#include "Core/HW/SI/SI_Device.h"
+
+#include "DolphinQt/Config/Mapping/GCPadWiiUConfigDialog.h"
+#include "DolphinQt/Config/Mapping/MappingWindow.h"
+#include "DolphinQt/Settings.h"
+
+#include "InputCommon/GCAdapter.h"
+
+static const std::map<SerialInterface::SIDevices, int> s_gc_types = {
+    {SerialInterface::SIDEVICE_NONE, 0},         {SerialInterface::SIDEVICE_GC_CONTROLLER, 1},
+    {SerialInterface::SIDEVICE_WIIU_ADAPTER, 2}, {SerialInterface::SIDEVICE_GC_STEERING, 3},
+    {SerialInterface::SIDEVICE_DANCEMAT, 4},     {SerialInterface::SIDEVICE_GC_TARUKONGA, 5},
+    {SerialInterface::SIDEVICE_GC_GBA, 6},       {SerialInterface::SIDEVICE_GC_KEYBOARD, 7}};
+
+static std::optional<int> ToGCMenuIndex(const SerialInterface::SIDevices sidevice)
+{
+  auto it = s_gc_types.find(sidevice);
+  return it != s_gc_types.end() ? it->second : std::optional<int>();
+}
+
+static std::optional<SerialInterface::SIDevices> FromGCMenuIndex(const int menudevice)
+{
+  auto it = std::find_if(s_gc_types.begin(), s_gc_types.end(),
+                         [=](auto pair) { return pair.second == menudevice; });
+  return it != s_gc_types.end() ? it->first : std::optional<SerialInterface::SIDevices>();
+}
+
+GamecubeControllersWidget::GamecubeControllersWidget(QWidget* parent) : QWidget(parent)
+{
+  CreateLayout();
+  LoadSettings();
+  ConnectWidgets();
+}
+
+void GamecubeControllersWidget::CreateLayout()
+{
+  m_gc_box = new QGroupBox(tr("GameCube Controllers"));
+  m_gc_layout = new QGridLayout();
+  m_gc_layout->setVerticalSpacing(7);
+  m_gc_layout->setColumnStretch(1, 1);
+
+  for (size_t i = 0; i < m_gc_groups.size(); i++)
+  {
+    auto* gc_label = new QLabel(tr("Port %1").arg(i + 1));
+    auto* gc_box = m_gc_controller_boxes[i] = new QComboBox();
+    auto* gc_button = m_gc_buttons[i] = new QPushButton(tr("Configure"));
+
+    for (const auto& item :
+         {tr("None"), tr("Standard Controller"), tr("GameCube Adapter for Wii U"),
+          tr("Steering Wheel"), tr("Dance Mat"), tr("DK Bongos"), tr("GBA"), tr("Keyboard")})
+    {
+      gc_box->addItem(item);
+    }
+
+    int controller_row = m_gc_layout->rowCount();
+    m_gc_layout->addWidget(gc_label, controller_row, 0);
+    m_gc_layout->addWidget(gc_box, controller_row, 1);
+    m_gc_layout->addWidget(gc_button, controller_row, 2);
+  }
+  m_gc_box->setLayout(m_gc_layout);
+
+  auto* layout = new QVBoxLayout;
+  layout->setMargin(0);
+  layout->setAlignment(Qt::AlignTop);
+  layout->addWidget(m_gc_box);
+  setLayout(layout);
+}
+
+void GamecubeControllersWidget::ConnectWidgets()
+{
+  for (size_t i = 0; i < m_gc_controller_boxes.size(); i++)
+  {
+    connect(m_gc_controller_boxes[i], qOverload<int>(&QComboBox::currentIndexChanged), this,
+            &GamecubeControllersWidget::SaveSettings);
+    connect(m_gc_controller_boxes[i], qOverload<int>(&QComboBox::currentIndexChanged), this,
+            &GamecubeControllersWidget::OnGCTypeChanged);
+    connect(m_gc_buttons[i], &QPushButton::clicked, this,
+            &GamecubeControllersWidget::OnGCPadConfigure);
+  }
+}
+
+void GamecubeControllersWidget::OnGCTypeChanged(int type)
+{
+  const auto* box = static_cast<QComboBox*>(QObject::sender());
+
+  for (size_t i = 0; i < m_gc_groups.size(); i++)
+  {
+    if (m_gc_controller_boxes[i] == box)
+    {
+      const int index = box->currentIndex();
+      m_gc_buttons[i]->setEnabled(index != 0 && index != 6);
+      return;
+    }
+  }
+
+  SaveSettings();
+}
+
+void GamecubeControllersWidget::OnGCPadConfigure()
+{
+  size_t index;
+  for (index = 0; index < m_gc_groups.size(); index++)
+  {
+    if (m_gc_buttons[index] == QObject::sender())
+      break;
+  }
+
+  MappingWindow::Type type;
+
+  switch (m_gc_controller_boxes[index]->currentIndex())
+  {
+  case 0:  // None
+  case 6:  // GBA
+    return;
+  case 1:  // Standard Controller
+    type = MappingWindow::Type::MAPPING_GCPAD;
+    break;
+  case 2:  // GameCube Adapter for Wii U
+    GCPadWiiUConfigDialog(static_cast<int>(index), this).exec();
+    return;
+  case 3:  // Steering Wheel
+    type = MappingWindow::Type::MAPPING_GC_STEERINGWHEEL;
+    break;
+  case 4:  // Dance Mat
+    type = MappingWindow::Type::MAPPING_GC_DANCEMAT;
+    break;
+  case 5:  // DK Bongos
+    type = MappingWindow::Type::MAPPING_GC_BONGOS;
+    break;
+  case 7:  // Keyboard
+    type = MappingWindow::Type::MAPPING_GC_KEYBOARD;
+    break;
+  default:
+    return;
+  }
+
+  MappingWindow* window = new MappingWindow(this, type, static_cast<int>(index));
+  window->setAttribute(Qt::WA_DeleteOnClose, true);
+  window->setWindowModality(Qt::WindowModality::WindowModal);
+  window->show();
+}
+
+void GamecubeControllersWidget::LoadSettings()
+{
+  for (size_t i = 0; i < m_gc_groups.size(); i++)
+  {
+    const std::optional<int> gc_index = ToGCMenuIndex(SConfig::GetInstance().m_SIDevice[i]);
+    if (gc_index)
+    {
+      m_gc_controller_boxes[i]->setCurrentIndex(*gc_index);
+      m_gc_buttons[i]->setEnabled(*gc_index != 0 && *gc_index != 6);
+    }
+  }
+}
+
+void GamecubeControllersWidget::SaveSettings()
+{
+  for (size_t i = 0; i < m_gc_groups.size(); i++)
+  {
+    const int index = m_gc_controller_boxes[i]->currentIndex();
+    const std::optional<SerialInterface::SIDevices> si_device = FromGCMenuIndex(index);
+    if (si_device)
+    {
+      SConfig::GetInstance().m_SIDevice[i] = *si_device;
+
+      if (Core::IsRunning())
+        SerialInterface::ChangeDevice(*si_device, static_cast<s32>(i));
+    }
+
+    m_gc_buttons[i]->setEnabled(index != 0 && index != 6);
+  }
+
+  if (GCAdapter::UseAdapter())
+    GCAdapter::StartScanThread();
+  else
+    GCAdapter::StopScanThread();
+
+  SConfig::GetInstance().SaveSettings();
+}
diff --git a/Source/Core/DolphinQt/Config/GamecubeControllersWidget.h b/Source/Core/DolphinQt/Config/GamecubeControllersWidget.h
new file mode 100644
index 0000000000..57f9322fab
--- /dev/null
+++ b/Source/Core/DolphinQt/Config/GamecubeControllersWidget.h
@@ -0,0 +1,39 @@
+// Copyright 2021 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <QWidget>
+
+#include <array>
+
+class QComboBox;
+class QHBoxLayout;
+class QGridLayout;
+class QGroupBox;
+class QPushButton;
+
+class GamecubeControllersWidget final : public QWidget
+{
+  Q_OBJECT
+public:
+  explicit GamecubeControllersWidget(QWidget* parent);
+
+private:
+  void LoadSettings();
+  void SaveSettings();
+
+  void OnGCTypeChanged(int state);
+  void OnGCPadConfigure();
+
+  void CreateLayout();
+  void ConnectWidgets();
+
+  // Gamecube
+  QGroupBox* m_gc_box;
+  QGridLayout* m_gc_layout;
+  std::array<QComboBox*, 4> m_gc_controller_boxes;
+  std::array<QPushButton*, 4> m_gc_buttons;
+  std::array<QHBoxLayout*, 4> m_gc_groups;
+};
diff --git a/Source/Core/DolphinQt/DolphinQt.vcxproj b/Source/Core/DolphinQt/DolphinQt.vcxproj
index 0f36194a9c..187b500e4c 100644
--- a/Source/Core/DolphinQt/DolphinQt.vcxproj
+++ b/Source/Core/DolphinQt/DolphinQt.vcxproj
@@ -58,6 +58,7 @@
     <ClCompile Include="Config\FilesystemWidget.cpp" />
     <ClCompile Include="Config\FreeLookWidget.cpp" />
     <ClCompile Include="Config\FreeLookWindow.cpp" />
+    <ClCompile Include="Config\GamecubeControllersWidget.cpp" />
     <ClCompile Include="Config\GameConfigEdit.cpp" />
     <ClCompile Include="Config\GameConfigHighlighter.cpp" />
     <ClCompile Include="Config\GameConfigWidget.cpp" />
@@ -231,6 +232,7 @@
     <QtMoc Include="Config\FilesystemWidget.h" />
     <QtMoc Include="Config\FreeLookWidget.h" />
     <QtMoc Include="Config\FreeLookWindow.h" />
+    <QtMoc Include="Config\GamecubeControllersWidget.h" />
     <QtMoc Include="Config\GameConfigHighlighter.h" />
     <QtMoc Include="Config\GameConfigWidget.h" />
     <QtMoc Include="Config\GeckoCodeWidget.h" />