I have a DFI board and the HSF which comes with it.
I have it in a Hiper chassis - running a 2.13G CPU - 1GB Ram, 160GB SATA drive etc - all working well.
Bar the fact the HSF makes a stupid whining sound when the top of the chassis is on it. It is something to do with the fan so close to the grill.
Is there any decent passive solutions?
The case is as thin as your normal DVD player...