Hmm.... it also says that mine has 100% but that could be some other info.... not so good with HWinfo64
😛 But it's weird that you don't get the GPU/CPU fan speed up :S
If you live in a place with dogs/cats or other animals then that can be a source for much dust/hair or it can be much dust in the air. And if the notebook is on 24/7 then the gathering of the dust will accumulate much faster.

This is the GPU exhaust, as you can see a lot of dust has gatherd in 8 months

And here you can see GPU fan disassembled and cleaned.
have more pics but I think these should show you how important it is to clean the fans once in a while
🙂EDIT:

Here I'm testing that the fans sounds normal, I noticed that I didn't place the metal thingy right on both fans (made a lot of vibrations sound) so I had to take them up again and then put it back on it's place (the attachments for it wasn't on it's place)
Asus G73SW-91058V 3D
- Intel Centrino Ultimate-N 6300
- BIOS 205