Intel Stock Core 2 Duo E4xxx Heatsink tested
 

Readers complain Frostytech doesn't have enough "reference" heatsinks to draw comparisons against. Good thing Frostytech has this review of a reference Intel Core 2 Duo E4xxx series socket 775 heatsink! The stock Intel Core 2 Duo E4400 heatsink is composed of two sections - the first an outer ring of extruded aluminum with 26mm long curved bifurcated (split) cooling fins, the second an internal 33mm diameter solid cylindrical aluminum heat spreading core. The aluminum slug at the center makes direct contact with the processor integrated heat spreader, conducting the heat it absorbs out to the larger fin surface area.

http://www.frostytech.com/articlevie...articleid=2335

I got a WORSE HSF with my 8400 E0, replaced it with a Freezer extreme just to see the pushpin mount fail to yield enough pressure (still does 3.6@1.2V, but the temps aren't good).