T400 Loud Fan

I bought a T400 three months ago and loved it at first but now am starting to have some problems. In the last couple of weeks the fan has started to almost always run at its top speed and there is always hot air coming out of the vents. Before, the fan barely ran and when it did run the air from the vents wasn't that warm. I took the keyboard off to see if there was any dust in the fan and it's completely clean. Can anyone tell me what is causing this? The fan also makes an annoying high pitched sound when running at top speed and I don't remember hearing this sound before.

 

Did you install some software recently that might cause the system to work very hard? What does Task Manager say for your CPU usage when this is happening? The T400 is the quietest notebook I’ve ever owned.

 

I've got a CPU usage monitor on my sidebar and it's just as low as it has always been. I also tried restoring to a Ghost image from 6 weeks ago to rule out any software problems. I agree that it was the quietest notebook I've ever owned when I first got it.

 

Chances are good it’s a hardware problem then… Call support.

 

If you're out of warrenty then try changing the thermal paste.

I bet the old thermal paste has dried up.
also follow the undervolting guide.

Also there could be a problem with the fan, maybe you need a new one.
Or you could *maybe* oil the old fan? (I'm not sure if that's a good idea).

 

I noticed the high pitch sound when loading a lot too. This is when I started to install vista 64 bit.

 

In three months? The thermal paste should be fine.

Also, you probably don't want to oil the fan, as it will most likely just make things worse, and even kill the fan.

Is this happening on discrete graphics mode, or integrated graphics mode? What power plan is your CPU set to in Power Manager (adaptive, lowest, maximal performance, etc)?

Try downloading Process Explorer (link in my signature) and see if Hardware Interrupts is consuming a large fraction of your CPU - this does not show up in Task Manager, but can still cause your CPU to run very hot.

 

Yeah, I'm not going to oil the fan lol.

Hmm...I forgot to mention that the system is much quieter in integrated mode than discrete mode which made me think that it has something to do with the graphics card. But I almost always run on discrete mode and this wasn't happening a month ago. The CPU was originally set to max performance but I changed it to adaptive when I started noticing the fan problem. Changing it to adaptive didn't change a thing.

Interrupts show up occasionally on process explorer but it's always under 5%. I don't think a 5% load once in a while could cause so much heat.

 

Also, I've noticed that although the fan is spinning very quickly and making a high pitched noise, it doesn't seem to be pushing out much air. I wonder why this is...

 

That's funny, cos I haven't heard the noise of the fan since my T400 arrived. I think it 3470's problem...