Without silent-block, here is the method
         for lowering the noise level of a Blue an White G3
         
         
         
         As usual, I cannot be responsible for any damage to
         your machines when you will experiment the following
         tutorial.
         
          1) 
          
         
         I took a special fabric used in kitchen's cupboard
         buiding which has the peculiarity to reduce the noises. The
         fabric roll is 150 cm X 50 cm: quite enough to reduce the
         noises for a lot of machines! It is made from a transparent
         plastic layer with several soft "bubbles" on its surface.
         
          Protection plastic sheets used in air freight packages
         can also be used, provide they have not too thick "bubbles".
         
          One can also use large plombing joints or rubber for
         reparing shoes soles!
         
          2) 
          
         
         Well, "Out Of Topic": The left yellow arrow shows the cap
         which hide the processor frequency's jumpers and the right
         arrow points to the jumpers set to 400 MHZ... instead of the
         original frequency 350 MHz.
         
          Unfortunately, trying to boost it to 450 MHZ just offers
         a "OpenFirmware" panel ;-)
         
          All this thanks to: http://perso.wanadoo.fr/keaps/overclock.html 
         and MacBidouille
         
          3) 
          
         
         Yellow arrows show the most principal noise's origins.
         
          From left to right and bottom to top:
         
          the CD drive 
            the power unit's fan 
            the mother board's fan 
            and finally the hard disks. 
         
         Blue arrows point to two screws to be removed to extract
         the big fan's craddle.
         
          4) 
          
         
         Once the screws have been removed, do not forget to
         disconnect the fan's power cable!
         
          5) 
          
         
         Yellow arrows on the top show the removed screws, yellow
         arrows on the bottom the locations where they were
         extracted.
         
          Blue arrow shows the fan's power cable connector.
         
          6) 
          
         
         The yellow arrow shows one of the screws which fixed the
         fan to its craddle. Unfortunately, they are screwed within
         the structure of the fan itsself: therefore they transmit
         the noises as well as the vibrations of the fan!
         
          And that's why we've to insulate them.
         
          7) 
          
         
         As the fan is dissambled, remove the fan sticker (if any)
         and put a little bit of sewing machine oil on the fan's axis
         (yellow arrow).
         
          Do not forget to place back the sticker!
         
          8) 
          
         
         I place the fan onto my fabric and takes both its
         internal and external footprints.
         
          9) 
          
         
         I can cut the fabric at the right dimensions..removing
         the part the internal footprint demarcates.
         
          10) 
          
         
         Now, create the screws holes: either with a specialized
         tool used by leather worker to make holes (here) or any
         other tool for making small holes.
         
          Blue arrow shows the small cutting out which has been
         made to avoid that the wind generated by the fan trills the
         plastic stuff.
         
          11) 
          
         
         With the residues of the footprint's cutting out process
         above, I cut small square pieces and creates a hole in it
         for the screws to pass through....
         
          12) 
          
         
         ... like this!
         
          13) 
          
         
         Il also cut out two other pieces with a rounded top.
         These will not so reduce noises but help me to put the fan
         back in place :-)
         
          14) 
          
         
         On the top of the picture, one can seen one of this screw
         which fix the fan and its "noise reducer".
         
          Now, let's operate the hard disk.
         
          Yellow arrows (from left to right) point to the IDE
         connector and the power cable connector: both of them have
         to be disconnected.
         
          Blue arrow points to the small screw which prevents the
         hard disk's craddle to slide to the right: this screw also
         has to be removed, as well as the small piece it maintains.
         
          15) 
          
         
         Yellow arrow points to one of the guides which lock the
         craddle.
         
          The blue one shows the move away sliding direction.
         
          16) 
          
         
         Craddle out: the 4 fixations screws.
         
          17) 
          
         
         So, same as above: small pieces cutted out in our fabric
         residues... small holes in them to allow the screws passign
         through.
         
          We place one of them above the craddle metal sheet, the
         other one under; the blue arrow shows on which side the hard
         disk is to be fixed on.
         
          18) 
          
         
         Our Noise reducers in place!
         
          19) 
          
         
         When putting the craddle back into place, take care that
         this craddle is inserted within its guides...otherwise noise
         will be higher that the level our homemade's reducers can
         absorb!!!
         
          And again, follow the above instructions in reverse order
         to re-assembly the whole stuff.
         
          Well, I did not have much time to operate the power
         unit's fan, neither the CD drive. Next tutorial perhaps ;-)
         
           
          
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