Been doing some research on HD cooler and I notice that there seem to be 2 kind. One had fans in front of the HD and blow air across the top and bottom of HD. Another has on that attaches to the bottom and blows air away on the bottom only. My thinking is does the bottom attachment do anything? Whenever I touch my HD it's hot on the top not where the chips are at. So is there any other 3.5 mountable Hd cooler I should consider? thanks