shouldn't an improperly installed heatsink and fan make the temps higher, not lower...?
that being said, when I improperly installed mine (stock Intel HS and fan) during the installation of my E6600, the temps started at 80c and the processor shut down a few seconds later at 90c...
I then remembered that when I cleaned off the old AS-5, if I wiped one way on the bottom of the heatsink (up and down) it smeared, and if I wiped the other direction (side to side) it came off, so I figured there were small grooves or something on the bottom of the heatsink, I rotated the heatsink and fan 90 degrees and voila, I turned it on and it was at 40c and started dropping...
I never knew that the way the heatsink and fan were oriented could affect the temps like that...