My X32 seems to have an accelerating (pulsing) fan problem.
The problem affects various Thinkpads and is described in detailed here:http://www.thinkwiki.org/wiki/Problem_with_fan_noise
In short, when the fan is on, every ~5 seconds there is a pulse noise, which is the fan accelerating momentarily, before returning to the normal speed. The problem seems to be present at all fan speeds (except 0 and maximum of course), and is quite unpleasant in a quiet room.
The aforementioned Thinkwiki page left me somewhat confused. On one hand, it says it is a firmware problem, and therefore a fan is not at fault. On the other hand, it seems to suggest that on other models (e.g., T43) changing the fan unit sometimes makes the problem go away. Several threads on these forums also suggest that, for instance: Any updates to solving the T43 fan pulsing problem?
The Linux-oriented Thinkwiki goes as far as suggesting an ACPI script to trick the embedded controller and override the firmware bug. Unfortunately, no similar tools exist for Windows, and TPFanControl seems to offer no solutions either.
I do have a spare X3x fan, but before I tear this poor X32 open yet again, I'd like to perhaps hear from folks with similar experience:
Have you encountered a pulsing fan problem on X31/X32?
If so, can replacing the fan solve the problem, or is it truly a FW/SW issue only?