I don't really know how to diagnose this before proceeding with a right decision to solve this problem. I know for sure that the air-flow should be much stronger at that high load of CPU. I can hear the sound fine (loud enough) but the air-flow is not much strong as expected (checked by placing my palm right in front of the air-flow exit). As before once I played one 3D game, the maximum temperature is just about 80 Celsius degree and at that high load the air-flow can blast your palm (placed around the air-flow exit) clearly BUT now I don't have that feeling. Also the maximum temperature now can reach 90 Celsius degree (so it's fairly logical to the weak air-flow). The air-flow sound is just like being clogged by some fluff.
I've just have my laptop (of course regard of its fan) cleaned but it's just like what I described above.
Could you give me some suggestions about what could be wrong with it? Replacing fan? upgrading the BIOS? something wrong with the fan controller? It's so ridiculous that the fan itself is just simple, its main parts are that the coils distributed correctly and there should be no way for it to function incorrectly (being weaken but not just stopped?). The most possible reason may involve the fan controller but still I cannot explain the air-flow sound (like being clogged by some fluff, cannot exit normally). I may have to buy a new laptop just because of its failed cooling system, its dedicated GPU becomes useless when it cannot run for a long time due to high-temperature issue. So bored, please help me, thanks a lot!