New fans in a G5 - Is it quieter? 

Thank you very much! Unfortunately, the front isn't magnetic. Cable splicing wasn't challenging, just be patient with the rubber casing for OEM wires, peeling and cutting it off. Super-gluing magnets on both the grill (from the inside) as well as on the fan isn't a bad idea to keep it in place. Then you could remove the fan at any time, really.

It's indeed important information, particularly the CFM. The bequiet fans run at a maximum of 1900rpm 12v at all times. Each 92mm fan does 33 CFM, each 80mm fan does 26.3 CFM. The 120mm blower style fan mounted on the front pulls air from the front and to the side under the logic board, where there's an air channel for the memory controller heatsink. There's another blower style fan on the hard drive bay assembly which pulls air from up top. Without the heatsink and fan up top, the MCP would overheat. The 120mm fan is there just to assist. Idle is 43-50c depending on room temperature. It's difficult to push this past 73c, and this happens mostly only when streaming youtube, or if I demonstrate opening a ton of apps at the same time.

thehouseofmoth.com/a-little-known-fact-about-the-power-mac-g5-and-what-to-do-with-this-information/