About a year ago my X200 (7454-96U) started exhibiting this behavior:
When I restart the system, either from full power-up or wake/resume, the CPU fan does not start approximately 1 out of every 3 times. The other 2 times the system starts normally and the fan operates as exepected. When the fan doesn't start the system eventually heats up to the point I have to power down, then restart. If I power up immediately, the BIOS displays "Fan Error" and halts before starting Windows. If I let it cool off, then power up, the fan usually starts correctly, Windows boots and all works well. Until the next time I restart.
I've tried all of the following suggestions made on the forum:
- * Installed the latest BIOS firmware (3.22 7XET72WW.)
* Reset all BIOS settings to factory defaults.
* Changed/enabled some of the BIOS security settings.
* Installed TPFanControl utility. When the fan doesn't start this program has no effect.
* Replaced the fan with a new one (and cleaned/dusted heat sink, etc.) This was quite painful and entailed disassembling the entire machine.
I believe it has to do with the BIOS (rather than Windows) because the fan should start immediately on power-on when the CPU is hot, and it doesn't. Also, it feels like a software/BIOS error rather than hardware because of the intermittent nature--if hardware you'd expect the fan to not work at all, or make a lot of noise. But it works just fine sometimes.
Does anyone have any other ideas I can try? I really love this notebook and don't want to trash it but this problem is making it very hard to use.