WD Firewire drives/Aftermarket FW drive

[animal]

I have two drives 120GB & 200GB inside an old G4 and after about 12 
hours they start complaining (likely overheating).  I've now positioned 
them apart which gives me and extra hour or two before the complaining 
starts.  However I bought 4 old ADS externals 3 years ago with fans for 
38$ each and the hard drives inside them never complain like the G4 
ones.  They're not used every day, but turned on for a long stretch at 
a time.  The fans are noisy but I'd be worried about running a hard 
drive without a fan.

Lynn