[ltp] T41 fan broken?

[Pintér Balázs]

Nate wrote:
> I'm unsure whether my fan has been working properly for a while now 
> because it just never seems to be on very fast. I'm running FC5, with 
> ibm_acpi.
>
> Today my fan mysteriously ramped up to what sounded like high speed 
> for the first time in 6+ months. About 6 months ago I sent it to IBM 
> with bad video memory and they replaced the main board (they said). At 
> the time the fan sounded rattly and but still pushed a lot of air when 
> it spooled up. Today the volume of air was not great however even 
> though it was loud. I was not doing anything unusual at the time. I 
> then read about ibm_acpi and wanted to see if I could get the fan to 
> ramp up again. I started playing multiple videos and managed to get 
> the temp up to around 85/86 degrees C, but the fan never changed 
> speeds noticeably.
>
> Below shows how quickly the cpu can cool down after I take the load off.
>
> [root@blackbox ~]# cat /proc/acpi/ibm/thermal; date
> temperatures:   85 50 34 65 36 -128 31 -128
> Sun Aug 13 21:59:56 EDT 2006
> [root@blackbox ~]# cat /proc/acpi/ibm/thermal; date
> temperatures:   59 50 34 61 36 -128 31 -128
> Sun Aug 13 22:00:43 EDT 2006
>
> To gauge the effectiveness of the fan, I let the cpu get up to 89 C by 
> turning off the fan and loading the cpu. I was afraid to let it go any 
> higher so I turned the fan to max (which is hardly perceptible, I'd 
> expect some significant noise) and the cpu temp went down to 86 and 
> stays constant for minutes. Is there a maximum cpu temp before 
> hardware protections shut the machine down or similar protection?
>
> I still have 6 months of warranty left on the machine. I think I'll 
> end up sending it in for a new fan, but I need the machine right now, 
> so it'll have to wait.
>
> Can anyone recognize these symptoms and can confirm this is unusual 
> behavior and a hardware problem?
>
> -Nathan
I had similar problem with my T40, the fan was wrong, because i had no 
warranty i ordered a new fan and replaced it in my machine. Since then 
everything is fine.
While i was waiting for the new fan I used cpufreq to lower the CPU 
speed to minimum, and turned off the fan, so my machine was silent and 
CPU temperature was 50 degrees.

Balazs Pinter