I wasnt getting good temperature with my heatsink so i wipe the thermal past using 70 percent isopropyl alcohol 3 times, using to many time isopropyl alcohol damage ur cpu?
I find the best way to remove and reapply thermal paste is with the kits you get from doing a dell warranty. My workplace has a few extra and I 'borrow' them sometimes to do my thermal paste.
70% tends to leave residue. Are you sure its not "rubbing" alcohol cause that would be really bad as it leaves oils. 90% or higher is recommended for isopropyl cleaner.