1. what do you mean by chimney?
2. there shouldnt be any fans on the outside of the case
3. Intake fans are usually placed at the front, bottom and side of case. exhaust fans placed and the back and top of case.
4. you can put cooling fans on ram but it wont be needed unless you are planning to overclock, or your case is getting hot. as for the hdd, there is no need to place fans on hdd they are designed to not need cooling.
Hope this helps