What i hear is the HD and not another fan. There has been a thread before about this issue and the conclusion was that the 6000d has one fan. fangui should be able to control 2 fans if it has two fans.
picard you are ok, you have reason.
i have taken apart my dell 6000d no second fan but then is it normal that my 7k60 make a noise like a 1000rpm fan?
(sorry for the photo ,i use my cell and not my digital camera )