Laptop shuts down on high fan speed.

[SomeGuyWithANumber]

An old laptop of mine (Acer Travelmate 5740G) which I use for network tasks has begun suddenly turning off when the fan turns on high. I originally believed this due to overheating, as the computer did not try and restart after it crashed, and the fan was noticeably louder for about 5 seconds beforehand. I have since cleaned out the fan and heatsink and replaced the thermal grease, this prevented the problem for a week or so but it is now reoccurring and removing the grease and reapplying it only fixes the problem for a short time. I have checked the temperature of components with HWiNFO64 and SpeedFan and the temperature of the GPU and CPU sit in the low 60C’s when the laptop shuts down. Currently the system will crash during startup and even if I leave it in the BIOS screen.

Specifications
Model: Acer TravelMate 5740G
OS: Win7
CPU: i5-430M
GPU: Radon HD 5470

What I’ve try so far:
Cleaned fan and replaced thermal grease. Fixed temporarily (1 day – 1 week)
Running on battery only and from the power point only. No effect.
Restoring the OS to the factory default. No effect.
Ran without fan plugged in. Shutdown still occurred at ~62C
left start-up in the BIOS screen. No effect
I am unable to chance the temperature thresholds for the fan in the Bios, or control it with SpeedFan

Any help in diagnosing the problem will be appreciated.

 

[webworkings]

It sounds like you need a new fan to me.

 

[SomeGuyWithANumber]

It sounds like you need a new fan to me.

Thanks for the reply, I have a new fan in the mail so I will update the post once it has arrived.
Just to elaborate, the fan does spin even when it is running on max. It also seems to jump from low to high cutting out the intermediate speeds. If it enters an intermediate speed the system cools effectively.
Is it common for a fan to crash a computer only at certain speeds?

 

[webworkings]

It is common for a computer to freak out over something not working correctly. They are very touchy. Just make sure when you change it out to clean off all the old thermal paste well and add fresh paste.

 

[SomeGuyWithANumber]

It is common for a computer to freak out over something not working correctly. They are very touchy. Just make sure when you change it out to clean off all the old thermal paste well and add fresh paste.

It was indeed the fan, I replaced it and everything runs smoothly now. It is reassuring to know that the computer shutdown because of panic attack from a fan error rather than because i fried my chips.

Thanks again for your help.

 

[webworkings]

Anytime.