How to tell if fan needs replacing or if its just dusty?

[Mickey_blu_eyes]

I have a PB tm97 laptop which randomly shuts down (especially when updating windows). I recently posted about checking it for overheating problem (see link at end). I used prime 95, which made it shut down after only a minute or two, so I was just going to start taking it apart to clean.

BUT (lol) how can i know its not actually the fan that's broken? It seems to work - hot air is coming out, and it looks like its spinning - BUT I already cleaned it. Plus speedfan doesnt show a fan as being present (I've tried getting the info, but its impossible to work out what motherboard I have)

Are there other ways than speedfan to test the fan?

Cheers very much!

 

[Mickey_blu_eyes]

Oops, forgot the link (its not useful actually anyway so won't bother putting it)