diff --git a/CHANGELOG.md b/CHANGELOG.md
index 344e2e0..74be366 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,19 @@ All notable changes to RigDoctor are recorded here. Format follows
 (`MAJOR.MINOR.PATCH`, pre-1.0). `__version__` and `pyproject.toml` must match the git
 release tag (so the auto-updater, D18, can compare versions).
 
+## [0.20.0] - 2026-05-22
+### Changed
+- **Reorganized navigation** into grouped sidebar sections — **Monitor** (Dashboard) ·
+  **Diagnose** (Games, Recordings, System Health, Tuning) · **System** (Inventory) · **App**
+  (Settings, Share) — so it's clear where to go.
+- **Renames for clarity:** *Health → System Health* (it's the overall 7-day system scan, not
+  per-game), *Environment → Tuning* (gaming tunables + fixes), *Logs → Recordings*,
+  *Setup → Settings*.
+- **Settings** absorbed **Notifications** (alerts) — app configuration (components/deps, alerts,
+  account access, uninstall) now lives in one page; Notifications is no longer a separate item.
+- **Recordings** is now a hub: pick which captured log to view (always-on capture, last
+  diagnostic, or a preserved crash), **Analyze crash** in place, alongside the recorder controls.
+
 ## [0.19.0] - 2026-05-22
 ### Added
 - **System-tray applet (M11, D13).** A tray icon whose menu shows live **CPU / GPU temp** and
diff --git a/docs/MODULES.md b/docs/MODULES.md
index ce0fddc..59300bd 100644
--- a/docs/MODULES.md
+++ b/docs/MODULES.md
@@ -67,12 +67,13 @@ Status: ⬜ not started · 🟦 designing · 🟨 in progress · ✅ done
   (`pending_crash`/`analyze_crash` + `health.check_previous_boot`). *Pending:* non-Steam
   launchers (Lutris/Heroic), GPU power-profile (PowerMizer) checks, and the zero-config watcher.
 - **M8 Alerting** — threshold/event notifications; integrates with the tray applet (M11).
-- **M10 Desktop GUI** — PySide6 graphical front-end over the core engine (dashboard, log
-  browser, report viewer, logger controls). Optional; adds the Qt dependency. *Bootstrapped
-  early (ahead of its Phase 4 slot) at the user's request:* dark-themed window with sidebar
-  nav, a live dashboard (circular gauges + collapsible per-subsystem cards, temperature-
-  colored values), and a **Recording/Logs page** with full M3 controls (start/stop/status +
-  post-crash report). Health/Inventory remain placeholders until M4/M5. GUI-first per D17.
+- **M10 Desktop GUI** — PySide6 graphical front-end over the core engine. Optional; adds the
+  Qt dependency. Dark-themed window with a **grouped sidebar** (Monitor / Diagnose / System /
+  App) over: **Dashboard** (live history graphs + per-subsystem cards), **Games** (M6 detection
+  + Run Diagnostic), **Recordings** (recorder controls + view/report any captured log + analyze
+  a crash), **System Health** (M4 scan), **Tuning** (M6 gaming tunables + fixes), **Inventory**
+  (M5), **Settings** (components/deps + alerts + account + uninstall), and **Share** (M12). A
+  global recording badge shows on every page. GUI-first per D17.
 - **M11 Tray applet** — `QSystemTrayIcon` menu-bar applet. *Implemented (`gui/tray.py`, D13):*
   the menu shows live M1 readouts (CPU temp, GPU temp, memory used/total) + a status line
   (Normal / Hot / GPU not responding), led by a **Run Diagnostic** submenu (per detected game →
diff --git a/pyproject.toml b/pyproject.toml
index 0354214..a9574f6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "rigdoctor"
-version = "0.19.0"
+version = "0.20.0"
 description = "Modular hardware monitoring & crash diagnostics for Linux gamers."
 readme = "README.md"
 requires-python = ">=3.11"
diff --git a/src/rigdoctor/__init__.py b/src/rigdoctor/__init__.py
index d9d095c..3aaf6a4 100644
--- a/src/rigdoctor/__init__.py
+++ b/src/rigdoctor/__init__.py
@@ -1,3 +1,3 @@
 """RigDoctor — modular hardware monitoring & crash diagnostics for Linux gamers."""
 
-__version__ = "0.19.0"
+__version__ = "0.20.0"
diff --git a/src/rigdoctor/gui/environment_page.py b/src/rigdoctor/gui/environment_page.py
index 3e04b85..ca239da 100644
--- a/src/rigdoctor/gui/environment_page.py
+++ b/src/rigdoctor/gui/environment_page.py
@@ -46,7 +46,7 @@ class EnvironmentPage(QWidget):
         root.setSpacing(16)
 
         header = QHBoxLayout()
-        title = QLabel("Environment")
+        title = QLabel("Tuning")
         title.setObjectName("PageTitle")
         header.addWidget(title)
         header.addStretch(1)
diff --git a/src/rigdoctor/gui/health_page.py b/src/rigdoctor/gui/health_page.py
index 13a6d42..b3a3dd0 100644
--- a/src/rigdoctor/gui/health_page.py
+++ b/src/rigdoctor/gui/health_page.py
@@ -32,7 +32,7 @@ class HealthPage(QWidget):
         root.setSpacing(16)
 
         header = QHBoxLayout()
-        title = QLabel("Health")
+        title = QLabel("System Health")
         title.setObjectName("PageTitle")
         header.addWidget(title)
         header.addStretch(1)
diff --git a/src/rigdoctor/gui/main_window.py b/src/rigdoctor/gui/main_window.py
index 76ae2d3..221356e 100644
--- a/src/rigdoctor/gui/main_window.py
+++ b/src/rigdoctor/gui/main_window.py
@@ -35,7 +35,6 @@ from .environment_page import EnvironmentPage
 from .games_page import GamesPage
 from .health_page import HealthPage
 from .inventory_page import InventoryPage
-from .notifications_page import NotificationsPage
 from .recorder_page import RecorderPage
 from .setup_page import SetupPage
 from .share_page import SharePage
@@ -43,7 +42,15 @@ from .theme import ACCENT, CRIT, GOOD, MUTED, TEXT
 from .tray import TrayIcon
 from .worker import SamplerWorker
 
-_NAV_ITEMS = ["Dashboard", "Logs", "Health", "Games", "Environment", "Inventory", "Setup", "Notifications", "Share"]
+# Sidebar grouped by intent. Each page name maps to a widget built in __init__; the stack is
+# filled in this order, so _PAGES.index(name) is the stack index.
+_NAV = [
+    ("Monitor", ["Dashboard"]),
+    ("Diagnose", ["Games", "Recordings", "System Health", "Tuning"]),
+    ("System", ["Inventory"]),
+    ("App", ["Settings", "Share"]),
+]
+_PAGES = [name for _section, names in _NAV for name in names]
 _ICON = Path(__file__).parent / "assets" / "rigdoctor.svg"
 
 
@@ -79,18 +86,21 @@ class MainWindow(QMainWindow):
         self.environment_page = EnvironmentPage()
         self.inventory_page = InventoryPage()
         self.setup_page = SetupPage()
-        self.notifications_page = NotificationsPage()
-        self.notifications_page.changed.connect(self._apply_alert_settings)
+        self.setup_page.changed.connect(self._apply_alert_settings)
         self.share_page = SharePage()
-        self._stack.addWidget(self.dashboard)            # 0 Dashboard
-        self._stack.addWidget(self.recorder_page)        # 1 Logs
-        self._stack.addWidget(self.health_page)          # 2 Health
-        self._stack.addWidget(self.games_page)           # 3 Games
-        self._stack.addWidget(self.environment_page)     # 4 Environment
-        self._stack.addWidget(self.inventory_page)       # 5 Inventory
-        self._stack.addWidget(self.setup_page)           # 6 Setup
-        self._stack.addWidget(self.notifications_page)   # 7 Notifications
-        self._stack.addWidget(self.share_page)           # 8 Share
+        # Page name → widget; the stack is filled in _PAGES order so indices line up.
+        self._pages = {
+            "Dashboard": self.dashboard,
+            "Games": self.games_page,
+            "Recordings": self.recorder_page,
+            "System Health": self.health_page,
+            "Tuning": self.environment_page,
+            "Inventory": self.inventory_page,
+            "Settings": self.setup_page,
+            "Share": self.share_page,
+        }
+        for name in _PAGES:
+            self._stack.addWidget(self._pages[name])
         content_layout.addWidget(self._stack)
 
         layout.addWidget(self._build_sidebar())
@@ -186,16 +196,22 @@ class MainWindow(QMainWindow):
         group = QButtonGroup(self)
         group.setExclusive(True)
         self._nav_buttons: dict[str, QPushButton] = {}
-        for i, name in enumerate(_NAV_ITEMS):
-            btn = QPushButton(name)
-            btn.setObjectName("NavButton")
-            btn.setCheckable(True)
-            btn.setCursor(Qt.CursorShape.PointingHandCursor)
-            btn.setChecked(i == 0)
-            btn.clicked.connect(lambda _checked, idx=i: self._stack.setCurrentIndex(idx))
-            group.addButton(btn, i)
-            v.addWidget(btn)
-            self._nav_buttons[name] = btn
+        for section, names in _NAV:
+            header = QLabel(section.upper())
+            header.setObjectName("NavSection")
+            v.addSpacing(8)
+            v.addWidget(header)
+            for name in names:
+                idx = _PAGES.index(name)
+                btn = QPushButton(name)
+                btn.setObjectName("NavButton")
+                btn.setCheckable(True)
+                btn.setCursor(Qt.CursorShape.PointingHandCursor)
+                btn.setChecked(idx == 0)
+                btn.clicked.connect(lambda _checked, i=idx: self._stack.setCurrentIndex(i))
+                group.addButton(btn, idx)
+                v.addWidget(btn)
+                self._nav_buttons[name] = btn
 
         v.addStretch(1)
         live = QLabel(f'<span style="color:{ACCENT};">●</span> <span style="color:{MUTED};">Live</span>')
@@ -287,7 +303,7 @@ class MainWindow(QMainWindow):
     def show_page(self, name: str) -> None:
         """Bring the window forward on a given page (used by the tray)."""
         if name in self._nav_buttons:
-            self._stack.setCurrentIndex(_NAV_ITEMS.index(name))
+            self._stack.setCurrentIndex(_PAGES.index(name))
             self._nav_buttons[name].setChecked(True)
         self.showNormal()
         self.raise_()
diff --git a/src/rigdoctor/gui/notifications_page.py b/src/rigdoctor/gui/notifications_page.py
deleted file mode 100644
index 1539888..0000000
--- a/src/rigdoctor/gui/notifications_page.py
+++ /dev/null
@@ -1,108 +0,0 @@
-"""Notifications page (M8 config): user-configurable alert settings."""
-
-from __future__ import annotations
-
-from PySide6.QtCore import Qt, Signal
-from PySide6.QtWidgets import (
-    QCheckBox,
-    QDoubleSpinBox,
-    QFrame,
-    QGridLayout,
-    QHBoxLayout,
-    QLabel,
-    QPushButton,
-    QVBoxLayout,
-    QWidget,
-)
-
-from ..config import load_config, update_config
-from ..core import alerts
-
-
-class NotificationsPage(QWidget):
-    changed = Signal()  # settings saved — main window re-applies them live
-
-    def __init__(self) -> None:
-        super().__init__()
-        self.setObjectName("Page")
-        root = QVBoxLayout(self)
-        root.setContentsMargins(20, 18, 20, 18)
-        root.setSpacing(16)
-
-        title = QLabel("Notifications")
-        title.setObjectName("PageTitle")
-        root.addWidget(title)
-
-        card = QFrame()
-        card.setObjectName("Card")
-        v = QVBoxLayout(card)
-        v.setContentsMargins(16, 14, 16, 14)
-        v.setSpacing(10)
-        head = QLabel("Alerts")
-        head.setStyleSheet("font-weight: 700; background: transparent;")
-        v.addWidget(head)
-
-        self._enabled = QCheckBox("Enable desktop notifications")
-        v.addWidget(self._enabled)
-
-        grid = QGridLayout()
-        grid.setHorizontalSpacing(12)
-        grid.setColumnStretch(2, 1)
-        self._gpu = self._spin()
-        self._cpu = self._spin()
-        grid.addWidget(QLabel("GPU temperature alert"), 0, 0)
-        grid.addWidget(self._gpu, 0, 1)
-        grid.addWidget(QLabel("CPU temperature alert"), 1, 0)
-        grid.addWidget(self._cpu, 1, 1)
-        v.addLayout(grid)
-
-        note = QLabel("GPU-lost and new-version alerts are included whenever notifications are enabled.")
-        note.setObjectName("Muted")
-        note.setWordWrap(True)
-        v.addWidget(note)
-
-        buttons = QHBoxLayout()
-        save = QPushButton("Save")
-        save.setObjectName("PrimaryButton")
-        save.clicked.connect(self._save)
-        test = QPushButton("Send test")
-        test.clicked.connect(self._test)
-        buttons.addWidget(save)
-        buttons.addWidget(test)
-        buttons.addStretch(1)
-        v.addLayout(buttons)
-        self._status = QLabel("")
-        self._status.setObjectName("Muted")
-        v.addWidget(self._status)
-
-        root.addWidget(card)
-        root.addStretch(1)
-        self._load()
-
-    @staticmethod
-    def _spin() -> QDoubleSpinBox:
-        spin = QDoubleSpinBox()
-        spin.setRange(40, 110)
-        spin.setDecimals(0)
-        spin.setSingleStep(1)
-        spin.setSuffix(" °C")
-        return spin
-
-    def _load(self) -> None:
-        cfg = load_config()
-        self._enabled.setChecked(bool(cfg.get("alerts_enabled", True)))
-        self._gpu.setValue(float(cfg.get("gpu_temp_alert", 90.0)))
-        self._cpu.setValue(float(cfg.get("cpu_temp_alert", 95.0)))
-
-    def _save(self) -> None:
-        update_config(
-            alerts_enabled=self._enabled.isChecked(),
-            gpu_temp_alert=self._gpu.value(),
-            cpu_temp_alert=self._cpu.value(),
-        )
-        self.changed.emit()
-        self._status.setText("Saved.")
-
-    def _test(self) -> None:
-        ok = alerts.notify("RigDoctor", "Test notification — alerts are working.")
-        self._status.setText("Test notification sent." if ok else "notify-send not found — install libnotify-bin (Setup).")
diff --git a/src/rigdoctor/gui/recorder_page.py b/src/rigdoctor/gui/recorder_page.py
index efcf50c..0744395 100644
--- a/src/rigdoctor/gui/recorder_page.py
+++ b/src/rigdoctor/gui/recorder_page.py
@@ -1,16 +1,19 @@
-"""Recording & Logs page (M3 in the GUI): start/stop/status + post-crash report.
+"""Recordings page (M3 in the GUI): recorder controls + view/report any captured log.
 
-Drives the same background recorder as the CLI via core.reccontrol, so the GUI and
-`rigdoctor record …` are interchangeable.
+Drives the same background recorder as the CLI via core.reccontrol, and surfaces the
+captured data — the always-on log, the last guided diagnostic, and a preserved hard-crash
+(which can be analyzed in place). One place to see what was captured and what it means.
 """
 
 from __future__ import annotations
 
+import threading
 import time
 
-from PySide6.QtCore import Qt, QTimer, QUrl
+from PySide6.QtCore import Qt, QTimer, QUrl, Signal
 from PySide6.QtGui import QDesktopServices, QFont
 from PySide6.QtWidgets import (
+    QComboBox,
     QDoubleSpinBox,
     QFrame,
     QHBoxLayout,
@@ -25,6 +28,7 @@ from .. import config
 from ..core import reccontrol
 from ..core.crashlog import summarize
 from ..render import format_headline, render_summary
+from .diagnostic_dialog import DiagnosticDialog
 from .theme import GOOD, MUTED, WARN
 
 
@@ -45,31 +49,30 @@ def _fmt_time(value, fmt="%Y-%m-%d %H:%M:%S") -> str:
 
 
 class RecorderPage(QWidget):
+    _analyzed = Signal(object)  # DiagnosticResult from a crash analysis
+
     def __init__(self) -> None:
         super().__init__()
         self.setObjectName("Page")
+        self._analyzed.connect(self._show_analysis)
         root = QVBoxLayout(self)
         root.setContentsMargins(20, 18, 20, 18)
         root.setSpacing(16)
 
-        title = QLabel("Recording")
+        title = QLabel("Recordings")
         title.setObjectName("PageTitle")
         root.addWidget(title)
 
         # --- Status + controls -------------------------------------------------
         status_card, status_layout = _panel("Status")
-
         self._state = QLabel("○ Not recording")
         self._state.setStyleSheet(f"color: {MUTED}; font-weight: 700; background: transparent;")
         status_layout.addWidget(self._state)
-
         self._info = QLabel("")
         self._info.setObjectName("Muted")
         status_layout.addWidget(self._info)
-
         self._latest = QLabel("")
         status_layout.addWidget(self._latest)
-
         self._warn = QLabel("")
         self._warn.setStyleSheet(f"color: {WARN}; font-weight: 600; background: transparent;")
         self._warn.setVisible(False)
@@ -97,19 +100,20 @@ class RecorderPage(QWidget):
         status_layout.addLayout(controls)
         root.addWidget(status_card)
 
-        # --- Report ------------------------------------------------------------
-        report_card = QFrame()
-        report_card.setObjectName("Card")
-        report_layout = QVBoxLayout(report_card)
-        report_layout.setContentsMargins(16, 14, 16, 14)
-        report_layout.setSpacing(10)
+        # --- Captured logs -----------------------------------------------------
+        report_card, report_layout = _panel("Captured logs")
         header = QHBoxLayout()
-        report_title = QLabel("Post-crash report")
-        report_title.setStyleSheet("font-weight: 700; background: transparent;")
-        header.addWidget(report_title)
-        header.addStretch(1)
+        header.addWidget(QLabel("Show:"))
+        self._source = QComboBox()
+        self._source.currentIndexChanged.connect(self._load_report)
+        header.addWidget(self._source, 1)
+        self._analyze_btn = QPushButton("Analyze crash")
+        self._analyze_btn.setObjectName("ActionButton")
+        self._analyze_btn.clicked.connect(self._analyze_crash)
+        self._analyze_btn.setVisible(False)
+        header.addWidget(self._analyze_btn)
         refresh_btn = QPushButton("Refresh")
-        refresh_btn.clicked.connect(self._load_report)
+        refresh_btn.clicked.connect(self._refresh_sources)
         header.addWidget(refresh_btn)
         report_layout.addLayout(header)
 
@@ -121,13 +125,12 @@ class RecorderPage(QWidget):
         report_layout.addWidget(self._report)
         root.addWidget(report_card, 1)
 
-        # Poll recorder status once a second (reflects CLI-driven sessions too).
         self._timer = QTimer(self)
         self._timer.setInterval(1000)
         self._timer.timeout.connect(self._refresh_status)
         self._timer.start()
         self._refresh_status()
-        self._load_report()
+        self._refresh_sources()
 
     # --- actions ---------------------------------------------------------------
     def _on_start(self) -> None:
@@ -139,12 +142,56 @@ class RecorderPage(QWidget):
         self._stop_btn.setEnabled(False)
         reccontrol.stop_background()
         QTimer.singleShot(600, self._refresh_status)
-        QTimer.singleShot(900, self._load_report)
+        QTimer.singleShot(900, self._refresh_sources)
 
     def _open_folder(self) -> None:
         config.LOG_DIR.mkdir(parents=True, exist_ok=True)
         QDesktopServices.openUrl(QUrl.fromLocalFile(str(config.LOG_DIR)))
 
+    # --- captured logs ---------------------------------------------------------
+    def _refresh_sources(self) -> None:
+        from ..core import diagnostic
+
+        current = self._source.currentData()
+        self._source.blockSignals(True)
+        self._source.clear()
+        self._source.addItem("Always-on capture", str(config.LOG_FILE))
+        if config.DIAG_LOG.exists():
+            self._source.addItem("Last diagnostic", str(config.DIAG_LOG))
+        if config.DIAG_CRASH.exists():
+            self._source.addItem("Crash (unanalyzed)", str(config.DIAG_CRASH))
+        # keep the previous selection if it's still present
+        idx = self._source.findData(current) if current else -1
+        self._source.setCurrentIndex(idx if idx >= 0 else 0)
+        self._source.blockSignals(False)
+        self._analyze_btn.setVisible(diagnostic.pending_crash() is not None)
+        self._load_report()
+
+    def _load_report(self) -> None:
+        path = self._source.currentData() or str(config.LOG_FILE)
+        summary = summarize(path, last_n=10)
+        self._report.setPlainText(render_summary(summary, log_path=path))
+
+    def _analyze_crash(self) -> None:
+        self._analyze_btn.setEnabled(False)
+        self._report.setPlainText("Analyzing the crash (final readings + system logs)…")
+        threading.Thread(target=self._work_analyze, daemon=True).start()
+
+    def _work_analyze(self) -> None:
+        from ..core import diagnostic
+
+        try:
+            result = diagnostic.analyze_crash()
+        except Exception:
+            result = None
+        self._analyzed.emit(result)
+
+    def _show_analysis(self, result) -> None:
+        self._analyze_btn.setEnabled(True)
+        if result is not None:
+            DiagnosticDialog(result, self).exec()
+        self._refresh_sources()
+
     # --- refresh ---------------------------------------------------------------
     def _refresh_status(self) -> None:
         pid = reccontrol.running_pid()
@@ -162,8 +209,10 @@ class RecorderPage(QWidget):
         self._interval.setEnabled(not running)
 
         if status:
+            game = status.get("game")
+            game_line = f"Game: {game}    " if game else ""
             self._info.setText(
-                f"Samples: {status.get('samples', 0)}    "
+                f"{game_line}Samples: {status.get('samples', 0)}    "
                 f"Started: {_fmt_time(status.get('started'))}    "
                 f"Updated: {_fmt_time(status.get('updated'), '%H:%M:%S')}\n"
                 f"Log: {status.get('log', config.LOG_FILE)}"
@@ -179,7 +228,3 @@ class RecorderPage(QWidget):
             self._info.setText("No recording yet. Press “Start recording”.")
             self._latest.setText("")
             self._warn.setVisible(False)
-
-    def _load_report(self) -> None:
-        summary = summarize(config.LOG_FILE, last_n=10)
-        self._report.setPlainText(render_summary(summary, log_path=config.LOG_FILE))
diff --git a/src/rigdoctor/gui/setup_page.py b/src/rigdoctor/gui/setup_page.py
index dcfb254..b72d790 100644
--- a/src/rigdoctor/gui/setup_page.py
+++ b/src/rigdoctor/gui/setup_page.py
@@ -1,4 +1,4 @@
-"""Setup page (M9 in the GUI): show environment + optional components, install missing."""
+"""Settings page: components/deps, alerts (M8), account access (token), and uninstall."""
 
 from __future__ import annotations
 
@@ -8,7 +8,10 @@ from PySide6.QtCore import Qt, QUrl, Signal
 from PySide6.QtGui import QDesktopServices
 from PySide6.QtWidgets import (
     QApplication,
+    QCheckBox,
+    QDoubleSpinBox,
     QFrame,
+    QGridLayout,
     QHBoxLayout,
     QLabel,
     QLineEdit,
@@ -21,7 +24,7 @@ from PySide6.QtWidgets import (
 )
 
 from .. import config
-from ..core import installer, sysenv, uninstall, updates
+from ..core import alerts, installer, sysenv, uninstall, updates
 from .theme import GOOD, MUTED, WARN
 
 
@@ -49,6 +52,7 @@ _BACKEND_DESC = {
 class SetupPage(QWidget):
     _installed = Signal(int, str)
     _upd_state = Signal(object)
+    changed = Signal()  # alert settings saved — main window re-applies them live
 
     def __init__(self) -> None:
         super().__init__()
@@ -60,7 +64,7 @@ class SetupPage(QWidget):
         root.setContentsMargins(20, 18, 20, 18)
         root.setSpacing(16)
 
-        title = QLabel("Setup")
+        title = QLabel("Settings")
         title.setObjectName("PageTitle")
         root.addWidget(title)
 
@@ -70,7 +74,7 @@ class SetupPage(QWidget):
         env_layout.addWidget(self._env)
         root.addWidget(env_card)
 
-        comp_card, comp_layout = _panel("Optional components")
+        comp_card, comp_layout = _panel("Components & dependencies")
         self._components = QVBoxLayout()
         self._components.setSpacing(6)
         comp_layout.addLayout(self._components)
@@ -86,6 +90,39 @@ class SetupPage(QWidget):
         comp_layout.addLayout(controls)
         root.addWidget(comp_card)
 
+        # Alerts (M8) — folded in from the old Notifications page.
+        alerts_card, alerts_layout = _panel("Notifications")
+        self._alerts_enabled = QCheckBox("Enable desktop notifications")
+        alerts_layout.addWidget(self._alerts_enabled)
+        grid = QGridLayout()
+        grid.setHorizontalSpacing(12)
+        grid.setColumnStretch(2, 1)
+        self._gpu_alert = self._spin()
+        self._cpu_alert = self._spin()
+        grid.addWidget(QLabel("GPU temperature alert"), 0, 0)
+        grid.addWidget(self._gpu_alert, 0, 1)
+        grid.addWidget(QLabel("CPU temperature alert"), 1, 0)
+        grid.addWidget(self._cpu_alert, 1, 1)
+        alerts_layout.addLayout(grid)
+        alerts_note = QLabel("GPU-lost and new-version alerts are included whenever notifications are enabled.")
+        alerts_note.setObjectName("Muted")
+        alerts_note.setWordWrap(True)
+        alerts_layout.addWidget(alerts_note)
+        alerts_buttons = QHBoxLayout()
+        save_alerts = QPushButton("Save")
+        save_alerts.setObjectName("PrimaryButton")
+        save_alerts.clicked.connect(self._save_alerts)
+        test_alerts = QPushButton("Send test")
+        test_alerts.clicked.connect(self._test_alerts)
+        alerts_buttons.addWidget(save_alerts)
+        alerts_buttons.addWidget(test_alerts)
+        alerts_buttons.addStretch(1)
+        self._alerts_status = QLabel("")
+        self._alerts_status.setObjectName("Muted")
+        alerts_buttons.addWidget(self._alerts_status)
+        alerts_layout.addLayout(alerts_buttons)
+        root.addWidget(alerts_card)
+
         # Account access (M13/M12): one Gitea token gates updates and session sharing.
         upd_card, upd_layout = _panel("Account access")
         hint = QLabel("A Gitea access token unlocks updates and session sharing. "
@@ -115,7 +152,7 @@ class SetupPage(QWidget):
         self._output = QTextEdit()
         self._output.setObjectName("Report")
         self._output.setReadOnly(True)
-        self._output.setMinimumHeight(180)
+        self._output.setMinimumHeight(160)
         self._output.setVisible(False)
         root.addWidget(self._output)
         root.addStretch(1)
@@ -129,8 +166,39 @@ class SetupPage(QWidget):
         root.addLayout(danger)
 
         self._refresh()
+        self._load_alerts()
         self._refresh_update_status()
 
+    # --- alerts (M8) ----------------------------------------------------------
+    @staticmethod
+    def _spin() -> QDoubleSpinBox:
+        spin = QDoubleSpinBox()
+        spin.setRange(40, 110)
+        spin.setDecimals(0)
+        spin.setSingleStep(1)
+        spin.setSuffix(" °C")
+        return spin
+
+    def _load_alerts(self) -> None:
+        cfg = config.load_config()
+        self._alerts_enabled.setChecked(bool(cfg.get("alerts_enabled", True)))
+        self._gpu_alert.setValue(float(cfg.get("gpu_temp_alert", 90.0)))
+        self._cpu_alert.setValue(float(cfg.get("cpu_temp_alert", 95.0)))
+
+    def _save_alerts(self) -> None:
+        config.update_config(
+            alerts_enabled=self._alerts_enabled.isChecked(),
+            gpu_temp_alert=self._gpu_alert.value(),
+            cpu_temp_alert=self._cpu_alert.value(),
+        )
+        self.changed.emit()
+        self._alerts_status.setText("Saved.")
+
+    def _test_alerts(self) -> None:
+        ok = alerts.notify("RigDoctor", "Test notification — alerts are working.")
+        self._alerts_status.setText(
+            "Test sent." if ok else "notify-send not found — install libnotify-bin above.")
+
     def _uninstall(self) -> None:
         box = QMessageBox(self)
         box.setIcon(QMessageBox.Icon.Warning)
diff --git a/src/rigdoctor/gui/theme.py b/src/rigdoctor/gui/theme.py
index ea23be9..a5f79c6 100644
--- a/src/rigdoctor/gui/theme.py
+++ b/src/rigdoctor/gui/theme.py
@@ -77,6 +77,7 @@ QPushButton#NavButton {{
 }}
 QPushButton#NavButton:hover {{ background: {CARD}; color: {TEXT}; }}
 QPushButton#NavButton:checked {{ background: {CARD}; color: #ffffff; font-weight: 600; }}
+QLabel#NavSection {{ color: {MUTED}; font-size: 10px; font-weight: 800; letter-spacing: 1px; padding: 2px 12px 0; }}
 
 #Card {{ background: {CARD}; border: 1px solid {CARD_BORDER}; border-radius: 12px; }}
 QPushButton#CardHeader {{
diff --git a/tests/test_gui_smoke.py b/tests/test_gui_smoke.py
index a65a9cb..786c45a 100644
--- a/tests/test_gui_smoke.py
+++ b/tests/test_gui_smoke.py
@@ -36,7 +36,8 @@ class GuiSmokeTests(unittest.TestCase):
              mock.patch.object(updates, "update_state", return_value=(updates.UP_TO_DATE, None, "")):
             window = mw.MainWindow()
         try:
-            self.assertEqual(len(window._nav_buttons), len(mw._NAV_ITEMS))
+            self.assertEqual(len(window._nav_buttons), len(mw._PAGES))
+            self.assertEqual(set(window._nav_buttons), set(mw._PAGES))
         finally:
             window._worker.stop()