GX620 Problem with the fan

Hi Dell Communities

 

First, please excuse me if i make some (or many :P) errors; i'm french and i'm not a very good pupil.

 

So, my problem is that when i turn on my Optiplex GX620, the fan make a horrible big and loud noise, and then continue normally, as if it has not done anything. This happen when i turn on my PC (i said), but also when i turn it on after deactivation.

At home, there's three other GX620 but no one do that at starting.

I think i should see something in the BIOS (A11) but it didn't find anything. (i didn't understand everything)

 

 

Please help me, this is very annoying, because everytime i turn on my computer, everyone in other room know it. -_-'

 

Thanks