Papst 8412 NGL 80mm fan (4 pin) (FG-003-PA)
Sintec Sleave Bearing for ultra-quiet operation
CFM = 19.4cfm
RPM = 1500
dBA = 12
Dimensions = 80x80x25
GlobalWin King Kong (SY-001-GL)
"Designed to fit inside a 5.25" Drive Bay, the King Kong has three 40mm fans moving a total of 14.7CFM. Each fan is daisy-chained with an extra pass-through power cable."
from //click here
Would this do the Job? They have more powerful rear fans but more noise!?