I tried to replace my old fan but had some trubble. I also replaced the original HDD with an 2.5" drive. So, it's really quit for now.
In fact, I wonder, if it's possible to leave the iMac G4 (800MHZ) without a fan, unless I figuered out my problem with the fan connectors. Ok, I know, the fan inside the iMac is not for nothing. But, is there anyone outside, who uses his iMac without a fan?