diff --git a/README.md b/README.md
index c7247cb..ebb2a9d 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Hardware Dashboard
 
-这是运行在 192.168.1.37 上的局域网设备监控与维护面板。页面提供 CPU、内存、双 P100 显卡、磁盘 SMART、性能历史曲线、硬件问题记录和定时任务管理。后端只使用 Python 标准库；前端使用原生 HTML、CSS 和 JavaScript，不依赖外部 CDN。
+这是运行在 192.168.1.37 上的局域网设备监控与维护面板。页面提供 CPU、内存、NVIDIA 显卡、磁盘 SMART、性能历史曲线、硬件问题记录和定时任务管理。支持在网页选择使用 1 张或 2 张显卡，支持夜间关机与 RTC 定时唤醒。后端只使用 Python 标准库；前端使用原生 HTML、CSS 和 JavaScript，不依赖外部 CDN。
 
 当前访问地址是 http://192.168.1.37:8090。定时任务可以执行服务器命令，必须使用独立的管理员账号登录。该账号与 SSH root 密码相互独立。
 
@@ -48,11 +48,11 @@ sudo cp config/hardware-watch.example.json /etc/hardware-watch.json
 sudo nano /etc/hardware-watch.json
 ```
 
-把 expected_gpu_count、GPU UUID 和磁盘名改成当前服务器的实际值。修改后重启监控采集服务。定时任务管理服务首次初始化会生成独立管理员密码文件；不要把生成的密码、任务数据库、日志或系统配置哈希提交到仓库。
+把 expected_gpu_count 和磁盘名改成当前服务器的实际值。若经常更换显卡，将 expected_gpu_uuids 设为空列表；也可在“计算显卡”卡片选择数量并保存。网页设置通过现有管理员登录验证，保存后同步到硬件采集器，重启后仍有效。定时任务管理服务首次初始化会生成独立管理员密码文件；不要把生成的密码、任务数据库、日志或系统配置哈希提交到仓库。
 
 ## 安全边界
 
-- 监控页面本身是只读的，可查看状态、曲线和日志。
+- 状态、曲线和日志无需登录；修改显卡数量需要管理员登录。
 - 定时任务能以 root 身份执行命令，新增、编辑、启用和立即执行均需要任务管理员登录。
 - 不要把这个服务直接暴露到公网。当前设计只适合可信局域网。
 - 远程访问应通过可信 VPN 或带 HTTPS 与额外认证的反向代理，而不是直接端口映射。
diff --git a/config/hardware-watch.example.json b/config/hardware-watch.example.json
index 70d695e..650f020 100644
--- a/config/hardware-watch.example.json
+++ b/config/hardware-watch.example.json
@@ -1,9 +1,6 @@
 {
   "expected_gpu_count": 2,
-  "expected_gpu_uuids": [
-    "GPU-00000000-0000-0000-0000-000000000001",
-    "GPU-00000000-0000-0000-0000-000000000002"
-  ],
+  "expected_gpu_uuids": [],
   "expected_disks": ["nvme0n1"],
   "gpu_warn_c": 85,
   "history_since": "7 days ago",
diff --git a/docs/DEPLOYMENT.zh-CN.md b/docs/DEPLOYMENT.zh-CN.md
index 9d2c281..4da378b 100644
--- a/docs/DEPLOYMENT.zh-CN.md
+++ b/docs/DEPLOYMENT.zh-CN.md
@@ -1,6 +1,6 @@
 # 192.168.1.37 监控与定时任务技术说明
 
-版本：v1.2，2026 年 11 月 4 日。
+版本：v1.3，2026 年 11 月 9 日。新增显卡数量设置和夜间节电计划，详见第 12 节。
 
 ## 1. 访问与登录
 
@@ -261,3 +261,49 @@ systemctl restart hardware-taskd.service
 | 未登录、错误来源、错误 CSRF | 分别被 HTTP 401／403 拒绝。 |
 
 这些测试仅打印信息或短暂等待，没有执行重启、关机、证书续签或修改现有业务配置。测试计划在交付前移除，历史中保留有“部署验证”字样的执行记录。
+
+## 12. 显卡数量与夜间节电（2026 年 11 月 9 日）
+
+### 显卡数量
+
+在“设备总览”的“计算显卡”卡片中，选择“1 张显卡”或“2 张显卡”，再点击“保存”。使用已有任务管理员账号登录后，设置保存到 `/etc/hardware-watch.json`，刷新网页、重启服务和重启服务器后仍有效。多个浏览器共用服务器上的设置。
+
+保存会更新 `expected_gpu_count` 并清空 `expected_gpu_uuids`。监控随后按 NVIDIA 显卡数量检查，不再要求原来的 P100 UUID；可更换为 V100 等受当前驱动支持的 NVIDIA 显卡。温度、供电、驱动异常、PCIe 通信错误继续检测。选择 2 张而实际仅检测到 1 张时，仍会报缺卡。
+
+页面通过 `/api/tasks/gpu-count` 调用已有 root 任务代理，沿用管理员会话、CSRF 和来源检查。普通网页进程仍无权写入 `/etc`。配置变更记录到任务管理审计表，同时触发一次硬件采集；页面每 10 秒刷新。
+
+配置变更不会删除历史告警。旧缺卡和旧 UUID 告警随采集恢复保留在历史中，不应再作为当前故障显示。
+
+### 每天 00:00 关机、06:00 开机
+
+页面“定时任务”中使用名称“夜间节电：00:00 关机，06:00 开机”。执行周期为北京时间每天 `00:00`，命令为：
+
+```bash
+/usr/bin/python3 /opt/hardware-dashboard/scripts/night-power-cycle.py
+```
+
+脚本先用 `rtcwake --utc --mode no` 设置当天北京时间 06:00 的 RTC 唤醒，并回读 `/sys/class/rtc/rtc0/wakealarm` 核对时间。确认成功后调用 `systemctl --no-block poweroff` 正常关机。服务器的硬件时钟采用 UTC；不要求存在 `/etc/adjtime`。
+
+脚本仅允许在北京时间 00:00 至 00:04 执行关机，避免白天点击“执行一次”时意外关机。若缺少 RTC 接口、设置闹钟失败或回读时间不符，本轮任务报错并保持开机。每天的任务均重新设置闹钟。系统定时器使用 `Persistent=false`，开机后不会补执行错过的关机任务。
+
+仅检查环境和下次唤醒时间：
+
+```bash
+/usr/bin/python3 /opt/hardware-dashboard/scripts/night-power-cycle.py --check
+```
+
+这个检查不设置闹钟，也不执行关机。真正开机由主板完成，需要 BIOS 支持并启用关机状态 RTC 唤醒，且电源持续接通。00:00 正在运行的计算任务会中断；关机期间无法访问监控网页。RTC 闹钟设置成功不能证明主板一定能从关机状态唤醒，完整效果应在首次夜间周期后确认。
+
+需要全天运行时，在页面停用这项计划。停用会取消后续关机调度，已设置的 RTC 闹钟仍可能保留。新增任务的“夜间节电”模板默认停用；如已有启用的同名任务，应编辑已有任务，避免重复添加。
+
+本次在 192.168.1.37 已创建并启用一项夜间节电任务。首次关机计划为北京时间 `2026-11-10 00:00`，RTC 闹钟已设置并回读确认为 `2026-11-10 06:00`。未在部署时执行实际关机。原代码、原显卡配置和任务数据库的备份位于 `/root/hardware-dashboard-backups/20261109-183339/`。
+
+### 新增文件与验证
+
+- `scripts/night-power-cycle.py`：RTC 设置、时间回读、关机及只读检查。
+- `tests/test_power_cycle.py`：验证时区、跨日、白天禁止关机、闹钟失败或不匹配时不关机。
+- `tests/test_tasks.py`：增加显卡数量输入校验、登录与 CSRF、其他配置保留及关机任务识别检查。
+
+技术栈仍为 Python 标准库、HTML、CSS、原生 JavaScript、SQLite 和 systemd；RTC 唤醒使用系统已有的 util-linux `rtcwake`。部署时需同步新增的 `scripts/` 目录，无需安装前端构建工具或第三方 Python 包。
+
+本次本地和服务器端均通过 22 项自动化测试，前端脚本语法检查通过。实际网页已验证单卡显示 `1/1`、无缺卡告警、仅显示一张显卡卡片；390 像素手机视口无横向溢出。登录后保存 1/2 张显卡及夜间模板填写流程使用浏览器模拟接口验证，没有执行真实关机。RTC 闹钟已在真实设备上设置并回读，完整关机唤醒周期尚待首次计划执行后验证。
diff --git a/scripts/night-power-cycle.py b/scripts/night-power-cycle.py
new file mode 100644
index 0000000..3aa5f3a
--- /dev/null
+++ b/scripts/night-power-cycle.py
@@ -0,0 +1,52 @@
+#!/usr/bin/python3
+"""At midnight, arm a 06:00 RTC alarm and request an orderly shutdown."""
+import argparse
+import datetime as dt
+from pathlib import Path
+import shutil
+import subprocess
+TZ = dt.timezone(dt.timedelta(hours=8), 'Asia/Shanghai')
+ALARM = Path('/sys/class/rtc/rtc0/wakealarm')
+
+
+def wake_time(now):
+    target = now.astimezone(TZ).replace(hour=6, minute=0, second=0, microsecond=0)
+    return target if target > now else target + dt.timedelta(days=1)
+
+
+def power_cycle(now, check=False):
+    target = wake_time(now)
+    print(f'当前时间：{now.astimezone(TZ).isoformat(timespec="seconds")}', flush=True)
+    print(f'计划唤醒：{target.isoformat(timespec="seconds")}', flush=True)
+    rtcwake = shutil.which('rtcwake')
+    systemctl = shutil.which('systemctl')
+    if not rtcwake or not systemctl or not ALARM.exists():
+        raise RuntimeError('未发现 RTC 唤醒接口或必要命令，本次不执行关机。')
+    if check:
+        print('检查完成；没有设置闹钟，也没有执行关机。', flush=True)
+        return
+    local = now.astimezone(TZ)
+    if local.hour != 0 or local.minute >= 5:
+        raise RuntimeError('此任务仅允许在北京时间 00:00–00:04 执行；本次不关机。')
+    # This server stores its hardware clock in UTC (timedatectl LocalRTC=no).
+    subprocess.run([rtcwake, '--utc', '--device', '/dev/rtc0', '--mode', 'no',
+                    '--time', str(int(target.timestamp()))], check=True, timeout=20)
+    alarm = int(ALARM.read_text().strip() or '0')
+    if abs(alarm - target.timestamp()) > 2:
+        raise RuntimeError('RTC 唤醒时间回读不一致，本次不执行关机。')
+    print('RTC 闹钟已确认，开始正常关机。正在运行的计算任务将停止。', flush=True)
+    subprocess.run([systemctl, '--no-block', 'poweroff'], check=True, timeout=20)
+
+
+def main():
+    parser = argparse.ArgumentParser(description='每天 00:00 关机，设置当天 06:00 RTC 唤醒。')
+    parser.add_argument('--check', action='store_true', help='仅检查环境和时间，不设置闹钟、不关机')
+    args = parser.parse_args()
+    try:
+        power_cycle(dt.datetime.now(TZ), args.check)
+    except (RuntimeError, OSError, ValueError, subprocess.SubprocessError) as exc:
+        parser.exit(1, f'夜间节电计划未完成：{exc}\n')
+
+
+if __name__ == '__main__':
+    main()
diff --git a/server.py b/server.py
index d9d6cc5..4edc73d 100644
--- a/server.py
+++ b/server.py
@@ -1,5 +1,5 @@
 #!/usr/bin/python3
-"""LAN-only, read-only hardware dashboard. Python 3.12 standard library."""
+"""LAN hardware dashboard with authenticated management. Python standard library."""
 import argparse
 import csv
 from contextlib import contextmanager
@@ -312,6 +312,10 @@ def sample(previous):
         faults.append(issue('journal', '硬件日志采集状态超过 3 分钟未更新，或系统时间异常。'))
     else:
         for value in hw.get('active', {}).values():
+            # Live GPU sampling uses the current configuration; the minute-level
+            # collector may still contain an alarm from before a settings change.
+            if value.get('category') in ('gpu_missing','gpu_identity'):
+                continue
             matched = next((x for x in faults if x['category'] == value.get('category')), None)
             if matched:
                 if value.get('severity') == 'ERROR':
@@ -332,7 +336,8 @@ def sample(previous):
               'cpu_threads': os.cpu_count(), 'cpu_sockets': cpu_sockets, 'cpu_temp': cpu_temp, 'load': list(os.getloadavg()),
               'memory': (1 - ram_available / ram_total) * 100, 'memory_total_gib': ram_total / 1073741824,
               'memory_available_gib': ram_available / 1073741824, 'gpus': gpu,
-              'expected_gpu_count': expected, 'gpu_warn_c': cfg.get('gpu_warn_c',85),
+              'expected_gpu_count': expected, 'gpu_count_only': not bool(cfg.get('expected_gpu_uuids')),
+              'gpu_warn_c': cfg.get('gpu_warn_c',85),
               'gpu_error': gpu_error, 'disk_temp': disk_temp, 'disks': disks, 'rates': rates,
               'device_map': device_map(gpu),
               'disk_used_gib': used / 1073741824, 'disk_total_gib': capacity / 1073741824,
@@ -695,7 +700,8 @@ class Handler(BaseHTTPRequestHandler):
         parsed=urlparse(self.path)
         actions={'/api/tasks/login':'auth.login','/api/tasks/logout':'auth.logout','/api/tasks/password':'auth.password',
                  '/api/tasks/preview':'tasks.preview','/api/tasks/save':'tasks.save','/api/tasks/enable':'tasks.enable',
-                 '/api/tasks/delete':'tasks.delete','/api/tasks/run':'tasks.run','/api/tasks/stop':'tasks.stop'}
+                 '/api/tasks/delete':'tasks.delete','/api/tasks/run':'tasks.run','/api/tasks/stop':'tasks.stop',
+                 '/api/tasks/gpu-count':'monitor.gpu_count'}
         if parsed.path not in actions:return self.send('Not found','text/plain',404)
         origin=self.headers.get('Origin','')
         host=self.headers.get('Host','')
diff --git a/static/app.js b/static/app.js
index 1ec7fb2..c2cc062 100644
--- a/static/app.js
+++ b/static/app.js
@@ -34,6 +34,11 @@ function renderStatus(data){
   metric('cpu-value',data.cpu,'%',1);meter('cpu-bar',data.cpu);$('cpu-threads').textContent=(data.cpu_sockets?data.cpu_sockets+' 路 CPU · ':'')+(data.cpu_threads||'—')+' 线程';$('cpu-temp').textContent=num(data.cpu_temp)+' °C';$('cpu-temp').title=data.cpu_name;
   metric('memory-value',data.memory,'%');meter('memory-bar',data.memory);$('memory-used').textContent=`${num(data.memory_total_gib-data.memory_available_gib,1)} / ${num(data.memory_total_gib,1)} GiB`;$('memory-free').textContent=num(data.memory_available_gib,1)+' GiB 可用';
   metric('gpu-count',data.gpus.length,`/ ${data.expected_gpu_count} 在线`);$('gpu-online-text').replaceChildren(el('i','dot'),document.createTextNode(data.gpus.length>=data.expected_gpu_count?'全部预期显卡可用':'显卡数量少于预期'));$('gpu-online-text').firstChild.style.background=data.gpus.length>=data.expected_gpu_count?colors.green:colors.red;$('gpu-type').textContent=data.gpus[0]?.name?.includes('P100')?'Tesla P100':'NVIDIA';
+  const gpuSelect=$('gpu-expected-count');
+  if(gpuSelect.dataset.pending===String(data.expected_gpu_count)){delete gpuSelect.dataset.pending;delete gpuSelect.dataset.dirty;}
+  if(!gpuSelect.dataset.dirty&&!gpuSelect.dataset.saving)gpuSelect.value=String(data.expected_gpu_count);
+  gpuSelect.disabled=!!gpuSelect.dataset.saving;$('gpu-config-save').disabled=!!gpuSelect.dataset.saving;
+  $('gpu-check-mode').textContent=data.gpu_count_only?'按所选数量检查，支持更换显卡':'当前按显卡身份检查';
   const disks=Object.values(data.smart||{}),diskBad=!data.hardware_stale&&disks.some(x=>x.passed===false||x.critical_warning),diskKnown=!data.hardware_stale&&disks.length&&disks.every(x=>x.available&&x.passed===true);
   $('disk-health').textContent=diskBad?'需要检查':diskKnown?'健康正常':'状态未知';$('disk-health').style.color=diskBad?colors.red:diskKnown?colors.green:colors.amber;
   $('disk-health-detail').textContent=diskKnown?'SMART 检查通过':diskBad?'请展开磁盘相关日志':'尚未取得完整 SMART 数据';$('disk-space').textContent=`已用 ${num(data.disk_used_gib,0)} / ${num(data.disk_total_gib,0)} GiB`;$('disk-temp').textContent=num(data.disk_temp)+' °C';
@@ -45,6 +50,7 @@ function renderStatus(data){
 }
 function renderGPUs(data){
   const holder=$('gpu-grid');holder.replaceChildren();
+  holder.classList.toggle('single',Math.max(data.gpus.length,data.expected_gpu_count)===1);
   const gpus=[...data.gpus].sort((a,b)=>a.uuid.localeCompare(b.uuid));
   gpus.forEach((gpu,index)=>{
     const card=el('article','gpu-card');card.style.setProperty('--accent',index%2?colors.amber:colors.blue);
diff --git a/static/index.html b/static/index.html
index b5ebf4d..6cd0ea0 100644
--- a/static/index.html
+++ b/static/index.html
@@ -44,7 +44,7 @@
   <section class="overview-grid" aria-label="设备关键指标">
     <article class="metric-card"><div class="card-top"><span>CPU 使用率</span><svg><use href="#cpu"/></svg></div><div class="metric-value" id="cpu-value">—<small>%</small></div><div class="meter"><i id="cpu-bar"></i></div><div class="metric-bottom"><span id="cpu-threads">正在读取</span><strong id="cpu-temp">— °C</strong></div></article>
     <article class="metric-card"><div class="card-top"><span>内存占用</span><svg><use href="#memory"/></svg></div><div class="metric-value" id="memory-value">—<small>%</small></div><div class="meter violet"><i id="memory-bar"></i></div><div class="metric-bottom"><span id="memory-used">— / — GiB</span><strong id="memory-free">— 可用</strong></div></article>
-    <article class="metric-card"><div class="card-top"><span>计算显卡</span><svg><use href="#gpu"/></svg></div><div class="metric-value" id="gpu-count">—<small>/ — 在线</small></div><div class="gpu-online-label" id="gpu-online-text"><i class="dot"></i>正在确认显卡状态</div><div class="metric-bottom"><span>按 UUID 识别显卡</span><strong id="gpu-type">NVIDIA</strong></div></article>
+    <article class="metric-card"><div class="card-top"><span>计算显卡</span><svg><use href="#gpu"/></svg></div><div class="metric-value" id="gpu-count">—<small>/ — 在线</small></div><div class="gpu-online-label" id="gpu-online-text"><i class="dot"></i>正在确认显卡状态</div><div class="gpu-config-controls"><label for="gpu-expected-count">计划使用</label><select id="gpu-expected-count" disabled><option value="1">1 张显卡</option><option value="2">2 张显卡</option></select><button type="button" id="gpu-config-save" disabled>保存</button></div><div class="metric-bottom"><span id="gpu-check-mode">选择数量后保存</span><strong id="gpu-type">NVIDIA</strong></div><p class="gpu-config-hint" id="gpu-config-hint" role="status">设置会保存到服务器；修改时需管理员登录。</p></article>
     <article class="metric-card"><div class="card-top"><span>系统磁盘</span><svg><use href="#disk"/></svg></div><div class="metric-value word" id="disk-health">—</div><div class="disk-health-detail" id="disk-health-detail">正在读取健康状态</div><div class="metric-bottom"><span id="disk-space">— / — GiB</span><strong id="disk-temp">— °C</strong></div></article>
   </section>
   <section class="section-heading compact"><div><h2>显卡实时状态</h2><span>高使用率表示正在计算，不等于硬件故障。</span></div><span class="subtle-pill">每 10 秒采样</span></section>
@@ -73,7 +73,7 @@
 <div class="toast" role="status" id="toast" hidden></div>
 <nav class="mobile-section-nav" aria-label="页面分区导航"><a href="#overview" data-section-link="overview" class="active"><svg><use href="#grid"/></svg>总览</a><a href="#trends" data-section-link="trends"><svg><use href="#trend"/></svg>趋势</a><a href="#events" data-section-link="events"><svg><use href="#logs"/></svg>问题</a><a href="#tasks" data-section-link="tasks"><svg><use href="#clock"/></svg>任务</a><a href="#guide" data-section-link="guide"><svg><use href="#help"/></svg>说明</a></nav>
 <dialog id="task-login-dialog" class="task-dialog small-dialog" aria-labelledby="task-login-heading"><form id="task-login-form"><div class="dialog-heading"><div><h2 id="task-login-heading">登录任务管理</h2><p>只有管理员可以创建和执行服务器任务。</p></div><button type="button" class="dialog-close" data-close-dialog="task-login-dialog" aria-label="关闭登录窗口">×</button></div><div class="dialog-content task-form-grid"><label class="full-field">账号<input id="task-login-user" value="admin" autocomplete="username" required></label><label class="full-field">管理密码<input id="task-login-password" type="password" autocomplete="current-password" required></label><p class="form-error full-field" id="task-login-error" role="alert" hidden></p></div><div class="dialog-footer"><span>此处不是 SSH root 密码。</span><button class="primary-button" type="submit">登录</button></div></form></dialog>
-<dialog id="task-editor-dialog" class="task-dialog" aria-labelledby="task-editor-heading"><form id="task-editor-form"><div class="dialog-heading"><div><h2 id="task-editor-heading">新增定时任务</h2><p>先填写执行内容，再设置周期。新任务默认停用，可先手动测试。</p></div><button type="button" class="dialog-close" data-close-dialog="task-editor-dialog" aria-label="关闭任务编辑">×</button></div><div class="dialog-content task-form-grid"><input id="task-id" type="hidden"><label>任务名称<input id="task-name" placeholder="例如：每天检查显卡" maxlength="80" required></label><label>快速模板<select id="task-template"><option value="custom">自定义任务</option><option value="hardware">显卡状态检查</option><option value="reboot">服务器定时重启</option><option value="certificate">SSL 证书续签示例</option></select></label><div class="template-hint full-field" id="task-template-hint" hidden></div><label>执行方式<select id="task-mode"><option value="command">直接输入命令</option><option value="script">粘贴脚本内容</option><option value="file">服务器上的脚本文件</option></select></label><label id="task-language-field">脚本解释器<select id="task-interpreter"><option value="bash">Bash / Shell</option><option value="python3">Python 3</option><option value="auto">按文件自身方式执行</option></select></label><label class="full-field" id="task-body-field"><span class="field-label-row"><span id="task-body-label">执行命令</span><button type="button" id="task-import-file" class="inline-button">导入本地脚本</button></span><textarea id="task-body" rows="7" spellcheck="false" placeholder="例如：/usr/bin/nvidia-smi" required></textarea><input id="task-upload" type="file" accept=".sh,.py,.txt" hidden></label><label class="full-field" id="task-path-field" hidden>服务器脚本的绝对路径<input id="task-path" placeholder="例如：/root/renew-cert.sh"></label><label class="full-field" id="task-arguments-field" hidden>脚本参数（可选）<input id="task-arguments" placeholder="例如：--check，带空格的参数请加引号"></label><div class="task-form-divider full-field"><strong>什么时候执行</strong><span>北京时间 UTC+8</span></div><label>执行周期<select id="task-cycle"><option value="daily">每天</option><option value="weekly">每周</option><option value="monthly">每月</option><option value="minutes">每隔若干分钟</option><option value="hours">每隔若干小时</option><option value="once">指定日期，仅执行一次</option><option value="cron">自定义 Cron（五段）</option></select></label><label data-task-cycle="daily weekly monthly">执行时间<input type="time" id="task-time" value="03:00"></label><label data-task-cycle="monthly" hidden>每月几日<input id="task-day" type="number" value="1" min="1" max="31"><small>当月没有该日期时会跳过。</small></label><label data-task-cycle="minutes hours" hidden>间隔数值<input id="task-every" type="number" value="60" min="1" max="1440"><small>从启用任务开始计时。</small></label><label class="full-field" data-task-cycle="once" hidden>指定执行时间<input id="task-once" type="datetime-local"></label><div class="weekday-field full-field" data-task-cycle="weekly" hidden><span>选择星期</span><div id="task-weekdays"><label><input type="checkbox" value="0" checked>一</label><label><input type="checkbox" value="1">二</label><label><input type="checkbox" value="2">三</label><label><input type="checkbox" value="3">四</label><label><input type="checkbox" value="4">五</label><label><input type="checkbox" value="5">六</label><label><input type="checkbox" value="6">日</label></div></div><label class="full-field" data-task-cycle="cron" hidden>Cron 表达式<input id="task-cron" value="0 3 * * *" spellcheck="false"><small>分 时 日 月 周，例如 0 3 * * * 表示每天 03:00。支持范围、列表和 */步长。</small></label><div class="schedule-preview full-field"><button type="button" class="text-button" id="task-preview">检查执行周期</button><span id="task-preview-text">错过执行时间不补跑；同一任务不会重叠执行。</span></div><details class="full-field task-advanced"><summary>高级设置（可选）</summary><div class="task-form-grid"><label>工作目录<input id="task-cwd" value="/root"></label><label>最长执行秒数<input id="task-timeout" type="number" value="1800" min="10" max="86400"></label><label class="full-field">备注<input id="task-notes" maxlength="400" placeholder="记录维护用途、域名或注意事项"></label></div></details><label class="task-enabled-field full-field"><input id="task-enabled" type="checkbox"><span>保存后启用，到计划时间自动执行<small>不勾选时仅保存，可先手动测试。执行身份：root。</small></span></label><p class="form-error full-field" id="task-editor-error" role="alert" hidden></p></div><div class="dialog-footer"><span>保存不会立即执行脚本。</span><div><button type="button" class="text-button" data-close-dialog="task-editor-dialog">取消</button><button type="submit" class="primary-button" id="task-save">保存任务</button></div></div></form></dialog>
+<dialog id="task-editor-dialog" class="task-dialog" aria-labelledby="task-editor-heading"><form id="task-editor-form"><div class="dialog-heading"><div><h2 id="task-editor-heading">新增定时任务</h2><p>先填写执行内容，再设置周期。新任务默认停用，可先手动测试。</p></div><button type="button" class="dialog-close" data-close-dialog="task-editor-dialog" aria-label="关闭任务编辑">×</button></div><div class="dialog-content task-form-grid"><input id="task-id" type="hidden"><label>任务名称<input id="task-name" placeholder="例如：每天检查显卡" maxlength="80" required></label><label>快速模板<select id="task-template"><option value="custom">自定义任务</option><option value="hardware">显卡状态检查</option><option value="reboot">服务器定时重启</option><option value="night_poweroff">夜间节电（00:00 关机 / 06:00 开机）</option><option value="certificate">SSL 证书续签示例</option></select></label><div class="template-hint full-field" id="task-template-hint" hidden></div><label>执行方式<select id="task-mode"><option value="command">直接输入命令</option><option value="script">粘贴脚本内容</option><option value="file">服务器上的脚本文件</option></select></label><label id="task-language-field">脚本解释器<select id="task-interpreter"><option value="bash">Bash / Shell</option><option value="python3">Python 3</option><option value="auto">按文件自身方式执行</option></select></label><label class="full-field" id="task-body-field"><span class="field-label-row"><span id="task-body-label">执行命令</span><button type="button" id="task-import-file" class="inline-button">导入本地脚本</button></span><textarea id="task-body" rows="7" spellcheck="false" placeholder="例如：/usr/bin/nvidia-smi" required></textarea><input id="task-upload" type="file" accept=".sh,.py,.txt" hidden></label><label class="full-field" id="task-path-field" hidden>服务器脚本的绝对路径<input id="task-path" placeholder="例如：/root/renew-cert.sh"></label><label class="full-field" id="task-arguments-field" hidden>脚本参数（可选）<input id="task-arguments" placeholder="例如：--check，带空格的参数请加引号"></label><div class="task-form-divider full-field"><strong>什么时候执行</strong><span>北京时间 UTC+8</span></div><label>执行周期<select id="task-cycle"><option value="daily">每天</option><option value="weekly">每周</option><option value="monthly">每月</option><option value="minutes">每隔若干分钟</option><option value="hours">每隔若干小时</option><option value="once">指定日期，仅执行一次</option><option value="cron">自定义 Cron（五段）</option></select></label><label data-task-cycle="daily weekly monthly">执行时间<input type="time" id="task-time" value="03:00"></label><label data-task-cycle="monthly" hidden>每月几日<input id="task-day" type="number" value="1" min="1" max="31"><small>当月没有该日期时会跳过。</small></label><label data-task-cycle="minutes hours" hidden>间隔数值<input id="task-every" type="number" value="60" min="1" max="1440"><small>从启用任务开始计时。</small></label><label class="full-field" data-task-cycle="once" hidden>指定执行时间<input id="task-once" type="datetime-local"></label><div class="weekday-field full-field" data-task-cycle="weekly" hidden><span>选择星期</span><div id="task-weekdays"><label><input type="checkbox" value="0" checked>一</label><label><input type="checkbox" value="1">二</label><label><input type="checkbox" value="2">三</label><label><input type="checkbox" value="3">四</label><label><input type="checkbox" value="4">五</label><label><input type="checkbox" value="5">六</label><label><input type="checkbox" value="6">日</label></div></div><label class="full-field" data-task-cycle="cron" hidden>Cron 表达式<input id="task-cron" value="0 3 * * *" spellcheck="false"><small>分 时 日 月 周，例如 0 3 * * * 表示每天 03:00。支持范围、列表和 */步长。</small></label><div class="schedule-preview full-field"><button type="button" class="text-button" id="task-preview">检查执行周期</button><span id="task-preview-text">错过执行时间不补跑；同一任务不会重叠执行。</span></div><details class="full-field task-advanced"><summary>高级设置（可选）</summary><div class="task-form-grid"><label>工作目录<input id="task-cwd" value="/root"></label><label>最长执行秒数<input id="task-timeout" type="number" value="1800" min="10" max="86400"></label><label class="full-field">备注<input id="task-notes" maxlength="400" placeholder="记录维护用途、域名或注意事项"></label></div></details><label class="task-enabled-field full-field"><input id="task-enabled" type="checkbox"><span>保存后启用，到计划时间自动执行<small>不勾选时仅保存，可先手动测试。执行身份：root。</small></span></label><p class="form-error full-field" id="task-editor-error" role="alert" hidden></p></div><div class="dialog-footer"><span>保存不会立即执行脚本。</span><div><button type="button" class="text-button" data-close-dialog="task-editor-dialog">取消</button><button type="submit" class="primary-button" id="task-save">保存任务</button></div></div></form></dialog>
 <dialog id="task-confirm-dialog" class="task-dialog small-dialog" aria-labelledby="task-confirm-heading"><div class="dialog-heading"><h2 id="task-confirm-heading">确认操作</h2></div><div class="dialog-content"><p id="task-confirm-message"></p><pre id="task-confirm-code" class="raw-log" hidden></pre></div><div class="dialog-footer"><button id="task-confirm-no" class="text-button">取消</button><button id="task-confirm-yes" class="primary-button">确认</button></div></dialog>
 <dialog id="task-runs-dialog" class="task-dialog log-dialog" aria-labelledby="task-runs-heading"><div class="dialog-heading"><div><h2 id="task-runs-heading">任务执行记录</h2><p>成功表示命令退出码为 0，具体业务结果仍以输出为准。</p></div><button type="button" class="dialog-close" data-close-dialog="task-runs-dialog" aria-label="关闭执行记录">×</button></div><div class="run-layout"><div id="task-runs-list" class="task-runs-list"></div><div class="task-run-output"><div id="task-run-meta" class="task-run-meta">选择一次执行，查看输出和错误。</div><pre id="task-run-output">尚未选择执行记录。</pre></div></div></dialog>
 <dialog id="task-password-dialog" class="task-dialog small-dialog" aria-labelledby="task-password-heading"><form id="task-password-form"><div class="dialog-heading"><h2 id="task-password-heading">修改任务管理密码</h2><button type="button" class="dialog-close" data-close-dialog="task-password-dialog" aria-label="关闭密码窗口">×</button></div><div class="dialog-content task-form-grid"><label class="full-field">原管理密码<input type="password" id="task-old-password" autocomplete="current-password" required></label><label class="full-field">新密码（至少 12 个字符）<input type="password" id="task-new-password" autocomplete="new-password" minlength="12" required></label><label class="full-field">再次输入新密码<input type="password" id="task-repeat-password" autocomplete="new-password" minlength="12" required></label><p class="form-error full-field" id="task-password-error" hidden></p></div><div class="dialog-footer"><span>修改后需要重新登录。</span><button type="submit" class="primary-button">保存新密码</button></div></form></dialog>
diff --git a/static/style.css b/static/style.css
index bc42935..6465f65 100644
--- a/static/style.css
+++ b/static/style.css
@@ -84,6 +84,12 @@ h1{font-size:28px;letter-spacing:.3px;font-weight:600;margin:7px 0 5px;line-heig
 .metric-bottom{display:flex;justify-content:space-between;align-items:center;margin-top:15px;gap:5px;white-space:nowrap;font-size:10px;color:#8195a3}
 .metric-bottom strong{color:#b9c6cd;font-size:10px;font-weight:400}
 .gpu-online-label,.disk-health-detail{font-size:11px;color:#a4b5bf;display:flex;gap:6px;align-items:center;height:4px;line-height:16px;margin-top:17px;margin-bottom:5px}
+.gpu-config-controls{display:flex;align-items:center;flex-wrap:wrap;gap:7px;margin-top:18px;font-size:11px;color:var(--muted)}
+.gpu-config-controls select,.gpu-config-controls button{font:inherit;color:#d9e7ed;background:#0f1b22;border:1px solid #38515f;border-radius:5px;padding:6px 8px;min-height:32px}
+.gpu-config-controls button{color:var(--green);cursor:pointer}
+.gpu-config-controls select:focus-visible,.gpu-config-controls button:focus-visible{outline:2px solid var(--green);outline-offset:2px}
+.gpu-config-controls :disabled{opacity:.5;cursor:wait}
+.gpu-config-hint{font-size:10px;line-height:1.6;color:var(--muted);margin:9px 0 0;overflow-wrap:anywhere}
 .disk-health-detail{height:10px;margin-top:5px}
 .section-heading{display:flex;align-items:center;justify-content:space-between;gap:18px;margin:34px 0 16px;scroll-margin-top:24px}
 .section-heading h2{font-size:19px;font-weight:600;letter-spacing:.4px;margin:5px 0}
@@ -94,6 +100,7 @@ h1{font-size:28px;letter-spacing:.3px;font-weight:600;margin:7px 0 5px;line-heig
 .compact span{font-size:10px;color:var(--muted)}
 .subtle-pill{border:1px solid var(--line);padding:3px 9px;border-radius:4px;white-space:nowrap;font:10px var(--mono)!important;color:#91a6b3!important}
 .gpu-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}
+.gpu-grid.single{grid-template-columns:minmax(0,1fr)}
 .gpu-card{border:1px solid var(--line);border-radius:9px;background:var(--panel);padding:19px 21px;position:relative;overflow:hidden;--accent:var(--blue)}
 .gpu-card::before{content:"";position:absolute;top:19px;bottom:19px;left:0;width:3px;background:var(--accent);border-radius:0 4px 4px 0}
 .gpu-card .gpu-head{display:flex;gap:10px;align-items:center}
diff --git a/static/tasks.js b/static/tasks.js
index 992e212..f667089 100644
--- a/static/tasks.js
+++ b/static/tasks.js
@@ -2,6 +2,7 @@
 (()=>{
 'use strict';
 let auth={logged_in:false},tasks=[],listBusy=false,listRefreshPending=false,selectedRun=null,runsTask=null,confirmResolve=null,runReadSequence=0;
+let pendingGpuSave=false;
 const states={running:['执行中','running'],success:['执行成功','success'],failed:['执行失败','failed'],timeout:['超时已停止','failed'],cancelled:['已停止','neutral'],interrupted:['执行被中断','warning']};
 function taskError(id,message){$(id).textContent=message;$(id).hidden=!message;}
 async function request(path,body){
@@ -32,9 +33,19 @@ function openLogin(){taskError('task-login-error','');$('task-login-password').v
 $('task-login-open').addEventListener('click',openLogin);
 $('task-login-form').addEventListener('submit',async event=>{
   event.preventDefault();const button=event.submitter;button.disabled=true;taskError('task-login-error','');
-  try{const result=await request('/login',{username:$('task-login-user').value.trim(),password:$('task-login-password').value});setAuth(result);$('task-login-password').value='';$('task-login-dialog').close();await refreshList();toast('已登录定时任务管理。');}
+  try{const result=await request('/login',{username:$('task-login-user').value.trim(),password:$('task-login-password').value});setAuth(result);$('task-login-password').value='';$('task-login-dialog').close();await refreshList();if(pendingGpuSave){pendingGpuSave=false;await saveGpuCount();}else toast('管理员已登录。');}
   catch(error){taskError('task-login-error',error.message);}finally{button.disabled=false;}
 });
+$('gpu-expected-count').addEventListener('change',()=>{$('gpu-expected-count').dataset.dirty='true';$('gpu-config-hint').textContent='尚未保存。保存后按所选数量检查，不再绑定原显卡。';});
+async function saveGpuCount(){
+  if(!auth.logged_in){pendingGpuSave=true;openLogin();$('gpu-config-hint').textContent='请使用现有管理员账号登录，登录后会保存本次选择。';return;}
+  const select=$('gpu-expected-count');select.dataset.saving='true';select.disabled=true;$('gpu-config-save').disabled=true;
+  try{const result=await request('/gpu-count',{expected_gpu_count:Number(select.value)});select.dataset.pending=String(result.expected_gpu_count);select.dataset.dirty='true';$('gpu-config-hint').textContent=result.message+' 最迟下次采样更新。';toast(result.message);await loadStatus();setTimeout(()=>{loadStatus();loadEvents();},1500);}
+  catch(error){$('gpu-config-hint').textContent=error.message;if(error.status===401){pendingGpuSave=true;openLogin();}else toast(error.message);}
+  finally{delete select.dataset.saving;select.disabled=false;$('gpu-config-save').disabled=false;}
+}
+$('gpu-config-save').addEventListener('click',saveGpuCount);
+$('task-login-dialog').addEventListener('close',()=>{if(!auth.logged_in)pendingGpuSave=false;});
 $('task-logout').addEventListener('click',async()=>{try{await request('/logout',{});setAuth({logged_in:false});document.querySelectorAll('.task-dialog[open]').forEach(dialog=>dialog.close());$('task-body').value='';$('task-run-output').textContent='';toast('已退出任务管理。');}catch(error){toast(error.message);}});
 document.querySelectorAll('[data-close-dialog]').forEach(button=>button.addEventListener('click',()=>$(button.dataset.closeDialog).close()));
 function confirmAction(title,message,code=''){
@@ -136,7 +147,7 @@ $('task-create').addEventListener('click',()=>openEditor().catch(error=>toast(er
 $('task-preview').addEventListener('click',async()=>{if(!$('task-editor-form').reportValidity())return;const button=$('task-preview');button.disabled=true;try{const result=await request('/preview',formDefinition());$('task-preview-text').textContent=result.schedule_label+'；预计下次：'+(result.next_run?when(result.next_run):'没有可计算的将来时间');}catch(error){$('task-preview-text').textContent=error.message;}finally{button.disabled=false;}});
 $('task-editor-form').addEventListener('submit',async event=>{
   event.preventDefault();taskError('task-editor-error','');const definition=formDefinition();
-  const dangerous=/\b(reboot|shutdown|poweroff|halt)\b|\binit\s+[06]\b/i.test(definition.body+' '+definition.path);
+  const dangerous=/\b(reboot|shutdown|poweroff|halt)\b|\binit\s+[06]\b|night-power-cycle\.py/i.test(definition.body+' '+definition.path);
   if(definition.enabled&&!await confirmAction(dangerous?'保存并启用重启／关机类任务？':'保存并启用任务？',dangerous?'此任务将在计划时间中断服务器业务。请确认脚本和执行时段已核对。':'保存后会按设置的周期执行，不会立即运行。',definition.mode==='file'?definition.path:definition.body.slice(0,800)))return;
   $('task-save').disabled=true;
   try{const result=await request('/save',definition);$('task-editor-dialog').close();toast(result.message);await refreshList();}
@@ -146,6 +157,7 @@ $('task-template').addEventListener('change',()=>{
   const type=$('task-template').value;$('task-enabled').checked=false;$('task-template-hint').hidden=type==='custom';
   if(type==='hardware'){$('task-name').value='检查显卡状态';$('task-mode').value='command';$('task-body').value='/usr/bin/nvidia-smi';$('task-cycle').value='daily';$('task-time').value='08:00';$('task-template-hint').textContent='只读取显卡状态，结果会出现在执行日志。可先保存为停用，再执行一次测试。';}
   if(type==='reboot'){$('task-name').value='服务器定时重启';$('task-mode').value='command';$('task-body').value='/usr/bin/systemctl reboot';$('task-cycle').value='weekly';$('task-time').value='03:00';$('task-weekdays').querySelectorAll('input').forEach(input=>input.checked=input.value==='6');$('task-template-hint').textContent='这条命令会重启整台服务器，正在运行的 GPU 任务会中断。模板默认停用，请先确认允许重启的时间。';}
+  if(type==='night_poweroff'){$('task-name').value='夜间节电：00:00 关机，06:00 开机';$('task-mode').value='command';$('task-body').value='/usr/bin/python3 /opt/hardware-dashboard/scripts/night-power-cycle.py';$('task-cycle').value='daily';$('task-time').value='00:00';$('task-notes').value='北京时间。先设置并回读当天 06:00 RTC 闹钟，再正常关机。需要主板支持关机状态 RTC 唤醒，并保持供电。';$('task-template-hint').textContent='每天 00:00 中断计算任务并关机，06:00 由主板唤醒。脚本只允许在 00:00–00:04 关机；检查环境请在命令末尾加 --check。若已有同名计划，请编辑已有计划，避免重复添加。模板默认停用。';}
   if(type==='certificate'){$('task-name').value='SSL 证书续签';$('task-mode').value='script';$('task-interpreter').value='bash';$('task-cycle').value='daily';$('task-time').value='03:10';$('task-body').value='#!/usr/bin/env bash\nset -euo pipefail\n# 先确认已有域名和续签配置，且没有其他重复的自动续签计划。\nif command -v certbot >/dev/null 2>&1; then\n  certbot renew --quiet\nelif [ -x /root/.acme.sh/acme.sh ]; then\n  /root/.acme.sh/acme.sh --cron --home /root/.acme.sh\nelse\n  echo "未检测到 Certbot 或 acme.sh，请先配置证书续签工具。" >&2\n  exit 1\nfi\n# 如需重新加载 Web 服务，请按实际服务另行配置 deploy-hook。';$('task-template-hint').textContent='这是续签示例，不会安装或配置域名。请先确认 Certbot／acme.sh 的现有配置，并检查是否已有续签任务。';}
   updateEditorFields();
 });
diff --git a/task_core.py b/task_core.py
index da95201..f36962b 100644
--- a/task_core.py
+++ b/task_core.py
@@ -189,7 +189,7 @@ def validate_definition(payload,check_paths=True):
     notes=str(payload.get('notes','')).strip()[:400]
     timeout=number(payload.get('timeout',1800),10,86400,'最长执行秒数')
     if not isinstance(payload.get('enabled',False),bool):raise TaskError('启用状态必须为是或否。')
-    dangerous=bool(re.search(r'\b(reboot|shutdown|poweroff|halt)\b|\binit\s+[06]\b',body+' '+path,re.I))
+    dangerous=bool(re.search(r'\b(reboot|shutdown|poweroff|halt)\b|\binit\s+[06]\b|night-power-cycle\.py',body+' '+path,re.I))
     return {'name':name,'mode':mode,'interpreter':interpreter,'body':body,'path':path,'arguments':arguments,
             'cwd':cwd,'schedule':payload.get('schedule',{}),'schedule_lines':lines,'schedule_label':label,
             'timeout':timeout,'notes':notes,'enabled':bool(payload.get('enabled',False)),
diff --git a/taskd.py b/taskd.py
index 783052f..c2adfa0 100644
--- a/taskd.py
+++ b/taskd.py
@@ -20,6 +20,7 @@ import time
 import task_core as core
 
 ADMIN=Path('/etc/hardware-task-admin.json')
+MONITOR_CONFIG=Path('/etc/hardware-watch.json')
 SOCKET=Path('/run/hardware-taskd/control.sock')
 SESSIONS={};ATTEMPTS={};GUARD=threading.RLock();MUTATE=threading.RLock()
 ALLOWED_UID=None
@@ -110,6 +111,7 @@ def dispatch(request):
             next_times=[time.time()+int(definition['schedule_lines'][0].split('=')[1][:-1])]
         return {'schedule_label':definition['schedule_label'],'next_run':min(next_times) if next_times else None,'dangerous':definition['dangerous']}
     with MUTATE:
+        if action=='monitor.gpu_count':return save_gpu_count(payload,client)
         if action=='tasks.save':return core.save_task(payload,client)
         if action=='tasks.enable':
             if not isinstance(payload.get('enabled'),bool):raise core.TaskError('启用状态格式不正确。')
@@ -119,6 +121,26 @@ def dispatch(request):
         if action=='tasks.stop':return core.stop_task(payload.get('id'),client)
     raise core.TaskError('不支持这个任务操作。',404)
 
+def save_gpu_count(payload,client=''):
+    count=payload.get('expected_gpu_count')
+    if type(count) is not int or count not in (1,2):
+        raise core.TaskError('请选择使用 1 张或 2 张显卡。')
+    config=json.loads(MONITOR_CONFIG.read_text())
+    if not isinstance(config,dict):raise core.TaskError('硬件监控配置格式不正确。',500)
+    config.update(expected_gpu_count=count,expected_gpu_uuids=[])
+    mode=MONITOR_CONFIG.stat().st_mode & 0o777
+    core.atom_write(MONITOR_CONFIG,json.dumps(config,ensure_ascii=False,indent=2)+'\n',mode)
+    # Replacement drops any ACL on the old file. Grant the dashboard's service
+    # group read access while keeping configuration writes restricted to root.
+    if pwd is not None and os.geteuid()==0:
+        import grp
+        os.chown(MONITOR_CONFIG,0,grp.getgrnam('hardware-watch').gr_gid)
+        os.chmod(MONITOR_CONFIG,0o640)
+    core.audit('gpu_count_changed',client=client,detail=f'expected_gpu_count={count}; identity=count')
+    refresh=core.execute(['systemctl','start','--no-block','hardware-watch.service'],check=False)
+    return {'expected_gpu_count':count,'message':f'已设置使用 {count} 张显卡；按数量检查，允许更换显卡。',
+            'refresh_pending':refresh.returncode==0}
+
 class Handler(socketserver.StreamRequestHandler):
     def handle(self):
         self.request.settimeout(25)
diff --git a/tests/test_power_cycle.py b/tests/test_power_cycle.py
new file mode 100644
index 0000000..a531cd8
--- /dev/null
+++ b/tests/test_power_cycle.py
@@ -0,0 +1,57 @@
+import datetime as dt
+import importlib.util
+from pathlib import Path
+import subprocess
+import unittest
+from unittest.mock import patch
+
+spec = importlib.util.spec_from_file_location('power_cycle', Path(__file__).resolve().parents[1] / 'scripts/night-power-cycle.py')
+power = importlib.util.module_from_spec(spec)
+spec.loader.exec_module(power)
+
+
+class PowerCycleTests(unittest.TestCase):
+    def setUp(self):
+        self.now = dt.datetime(2026, 11, 10, 0, 0, 1, tzinfo=power.TZ)
+
+    def test_six_am_uses_shanghai_time_even_when_input_is_utc(self):
+        target = power.wake_time(self.now.astimezone(dt.timezone.utc))
+        self.assertEqual(target.isoformat(), '2026-11-10T06:00:00+08:00')
+        tomorrow = power.wake_time(self.now.replace(hour=18))
+        self.assertEqual(tomorrow.isoformat(), '2026-11-11T06:00:00+08:00')
+
+    def test_dry_check_and_daytime_run_never_shutdown(self):
+        with patch.object(power.shutil, 'which', side_effect=lambda name: '/usr/bin/' + name), \
+             patch.object(Path, 'exists', return_value=True), \
+             patch.object(power.subprocess, 'run') as run:
+            power.power_cycle(self.now, check=True)
+            run.assert_not_called()
+            with self.assertRaises(RuntimeError):
+                power.power_cycle(self.now.replace(hour=18))
+            run.assert_not_called()
+
+    def test_shutdown_only_after_alarm_is_armed_and_verified(self):
+        target = power.wake_time(self.now)
+        with patch.object(power.shutil, 'which', side_effect=lambda name: '/usr/bin/' + name), \
+             patch.object(Path, 'exists', return_value=True), \
+             patch.object(Path, 'read_text', return_value=str(int(target.timestamp()))), \
+             patch.object(power.subprocess, 'run') as run:
+            power.power_cycle(self.now)
+            self.assertEqual(run.call_count, 2)
+            self.assertIn('no', run.call_args_list[0].args[0])
+            self.assertIn(str(int(target.timestamp())), run.call_args_list[0].args[0])
+            self.assertEqual(run.call_args_list[1].args[0], ['/usr/bin/systemctl', '--no-block', 'poweroff'])
+
+    def test_failed_or_wrong_alarm_prevents_shutdown(self):
+        with patch.object(power.shutil, 'which', side_effect=lambda name: '/usr/bin/' + name), \
+             patch.object(Path, 'exists', return_value=True), \
+             patch.object(Path, 'read_text', return_value='0'), \
+             patch.object(power.subprocess, 'run') as run:
+            with self.assertRaises(RuntimeError):
+                power.power_cycle(self.now)
+            self.assertEqual(run.call_count, 1)
+            run.reset_mock()
+            run.side_effect = subprocess.CalledProcessError(1, 'rtcwake')
+            with self.assertRaises(subprocess.CalledProcessError):
+                power.power_cycle(self.now)
+            self.assertEqual(run.call_count, 1)
diff --git a/tests/test_tasks.py b/tests/test_tasks.py
index c2bef3c..b8eb490 100644
--- a/tests/test_tasks.py
+++ b/tests/test_tasks.py
@@ -96,4 +96,35 @@ class TaskTests(unittest.TestCase):
         self.assertTrue(result['tail_only']);self.assertEqual(len(result['output']),131072)
         with self.assertRaises(core.TaskError):core.read_run('../password')
 
+    def test_gpu_count_requires_login_csrf_and_preserves_other_config(self):
+        config=Path(self.temp.name)/'hardware-watch.json'
+        config.write_text(json.dumps({'expected_gpu_count':2,'expected_gpu_uuids':['old-p100'],
+                                      'expected_disks':['nvme0n1'],'gpu_warn_c':85}))
+        with patch.object(taskd,'MONITOR_CONFIG',config),patch.object(core,'execute') as execute:
+            execute.return_value.returncode=0
+            request={'action':'monitor.gpu_count','payload':{'expected_gpu_count':1}}
+            with self.assertRaises(core.TaskError) as error:taskd.dispatch(request)
+            self.assertEqual(error.exception.status,401)
+            login=taskd.login({'username':'admin','password':'only-a-test-password'},'qa')
+            request['token']=login['token']
+            with self.assertRaises(core.TaskError) as error:taskd.dispatch(request)
+            self.assertEqual(error.exception.status,403)
+            request['csrf']=login['csrf']
+            for bad in [True,0,3,'1',1.0]:
+                request['payload']={'expected_gpu_count':bad}
+                with self.subTest(value=bad),self.assertRaises(core.TaskError):taskd.dispatch(request)
+            for count in (1,2):
+                request['payload']={'expected_gpu_count':count}
+                taskd.dispatch(request)
+                saved=json.loads(config.read_text())
+                self.assertEqual(saved['expected_gpu_count'],count)
+                self.assertEqual(saved['expected_gpu_uuids'],[])
+                self.assertEqual(saved['expected_disks'],['nvme0n1'])
+                self.assertEqual(saved['gpu_warn_c'],85)
+            self.assertEqual(execute.call_count,2)
+
+    def test_night_cycle_is_identified_as_shutdown_task(self):
+        definition=core.validate_definition(self.definition(body='/usr/bin/python3 /opt/hardware-dashboard/scripts/night-power-cycle.py'),check_paths=False)
+        self.assertTrue(definition['dangerous'])
+
 if __name__=='__main__':unittest.main(verbosity=2)