diff --git a/src/duckstation-qt/gamepropertiesdialog.cpp b/src/duckstation-qt/gamepropertiesdialog.cpp
index d5f0846bb..be868e215 100644
--- a/src/duckstation-qt/gamepropertiesdialog.cpp
+++ b/src/duckstation-qt/gamepropertiesdialog.cpp
@@ -311,6 +311,7 @@ void GamePropertiesDialog::populateGameSettings()
 
   populateBooleanUserSetting(m_ui.userEnableCPUClockSpeedControl, gs.cpu_overclock_enable);
   populateBooleanUserSetting(m_ui.userEnable8MBRAM, gs.enable_8mb_ram);
+  m_ui.userCPUClockSpeed->setEnabled(m_ui.userEnableCPUClockSpeedControl->checkState() != Qt::Unchecked);
   updateCPUClockSpeedLabel();
 
   if (gs.cdrom_read_speedup.has_value())
@@ -567,7 +568,7 @@ void GamePropertiesDialog::connectUi()
   connectBooleanUserSetting(m_ui.userEnableCPUClockSpeedControl, &m_game_settings.cpu_overclock_enable);
   connectBooleanUserSetting(m_ui.userEnable8MBRAM, &m_game_settings.enable_8mb_ram);
   connect(m_ui.userEnableCPUClockSpeedControl, &QCheckBox::stateChanged, this,
-          &GamePropertiesDialog::updateCPUClockSpeedLabel);
+          &GamePropertiesDialog::onEnableCPUClockSpeedControlChecked);
 
   connect(m_ui.userCPUClockSpeed, &QSlider::valueChanged, [this](int value) {
     if (value == 100)
@@ -856,11 +857,18 @@ void GamePropertiesDialog::connectUi()
 
 void GamePropertiesDialog::updateCPUClockSpeedLabel()
 {
-  const int percent = m_ui.userCPUClockSpeed->value();
+  const int percent =
+    m_ui.userEnableCPUClockSpeedControl->checkState() != Qt::Unchecked ? m_ui.userCPUClockSpeed->value() : 100;
   const double frequency = (static_cast<double>(System::MASTER_CLOCK) * static_cast<double>(percent)) / 100.0;
   m_ui.userCPUClockSpeedLabel->setText(tr("%1% (%2MHz)").arg(percent).arg(frequency / 1000000.0, 0, 'f', 2));
 }
 
+void GamePropertiesDialog::onEnableCPUClockSpeedControlChecked(int state)
+{
+  m_ui.userCPUClockSpeed->setEnabled(state != Qt::Unchecked);
+  updateCPUClockSpeedLabel();
+}
+
 void GamePropertiesDialog::onUserAspectRatioChanged()
 {
   const int index = m_ui.userAspectRatio->currentIndex();
diff --git a/src/duckstation-qt/gamepropertiesdialog.h b/src/duckstation-qt/gamepropertiesdialog.h
index d42ebfd85..be4c83395 100644
--- a/src/duckstation-qt/gamepropertiesdialog.h
+++ b/src/duckstation-qt/gamepropertiesdialog.h
@@ -37,6 +37,7 @@ private Q_SLOTS:
   void onVerifyDumpClicked();
   void onExportCompatibilityInfoClicked();
   void updateCPUClockSpeedLabel();
+  void onEnableCPUClockSpeedControlChecked(int state);
 
 private:
   void setupAdditionalUi();