SpeedFan是一个免费但功能强大的硬件监控工具，除了常见的CPU温度、硬盘温度及风扇转速监测外，它还具有调节风扇转速的功能（包括手动调节和自动调节），并且可以对CPU进行软超频（原理类似CPUFSB和ClockGen）。个人感觉其“图表”功能很实用，可以让我们通过不断变化的曲线直观地了解到CPU温度、硬盘温度及风扇转速的总体走势。用在超频时监测CPU温度及风扇转速变化情况很适合，当然也可以用它来监测一下如今很火的Prescott核心赛扬D处理器，看看其待机温度和满负荷运行温度到底如何。 当然，大多数主板都有其厂家推出的专用监控软件，不过，将SpeedFan作为辅助软件来使用也是不错的选择（特别是那些杂牌主板）需要注意的一点是，其监测出的各项数据与MotherBoard Monitor和Hardware Sensors Monitor一致，但与个别主板专用监测软件监测出的数据有少许出入（可能与主板使用的BIOS版本有关）。

SpeedFan更新日志：

-greatly improved nVidia video card support
-added full access to hardware monitor chips available on several nVidia video cards (enabled I2C writes to allow fan speed control too)
-improved Intel QST support
-Intel QST now checks first for 2.0, then falls back to 1.0, if needed
-added support for external USB drives using JMicron controllers
-fixed fan speed computation for several Analog Devices chips (ADM1027, ADT7463, ADT7475, ADT7476, ADT7468, ADT7473, ADT7490) when configured for non standard number of pulses per revolution
-MUTEXes used to synchronize with other tools while accessing buses are now defined Global
-fixed CPU usage bars size on the main window
-enabled SMBus access on ICH10 and ICH10R, if needed
-if SpeedFan service is unavailable, a message dialog is shown and the program stops running
-added scan exceptions for Asus P5N-T DELUXE and Intel DX58SO
-SEND REPORT now includes a list of ACPI devices found