If you are running a serious rig, are simply concerned with the physical health of your PC, or have a sudden urge to know the internal temp. of your machine, look no further than CPUID’s HWMonitor.
This free app provides real time information regarding the state of your machines internals (main processor, graphics card, hard drives, etc), displaying the current voltages, temperatures, and fans speeds from your computer’s built-in sensors.
Besides the wonderful price (see: zero dollars), this useful piece of software doesn’t require any installation; instead, it operates as a standalone executable. Best of all, it works on both 32 and 64-bit operating systems.