microprocessor thermal-cooling assembly (is this a fan?)

That model number means next to nothing. Please post the i model number, 8000, 8100, 8200, 8500, 8600 and so on.

No the fan is not suposed to be that loud.

The fan is gonna be fairly loud, but not unbearably so. Since it's small, it has to be fast to move enough air. And Speed = Noise with fans.  Post your Inspiron Number, should be somewhere near the keyboard, and someone will be able to give you a first hand opinion.

The microprocessor thermal cooling unit is different than the fan. The part number for the thermal cooling unit/heat sink is 6G141 (PIPE,HT,THN,FINS,CABN,PACO) for an I8200. The fan part number is 6F858. You need to check the part numbers for other systems with Dell spare parts. I suggest calling the small business line instead of the home/home office parts line because the small business line's warehouse has more parts in stock whereas the warehouse that supplies the home/home office division is out of the microprocessor thermal cooling units.

--Sam 

I8200, 2.2 Ghz P-4M, 384 mb ram, 20 Gig HD, dvd rom, Truemobile 1300 b/g wireless, 32 mb Nvidia GeForce video

doesn't matter where s/he calls, they go by the account information on the system.  If its a personal/home user account s/he'll have to talk fast to get anything out of the small business people.

inspiron 1100, thanks