The Sempron 140 is a 45W CPU. There weren't too many Athlon X2 CPUs that were 45W, most were 65W CPUs. Unless you have a model with a "e" at the end, that heat sink wasn't designed to handle the heat of the CPU. Don't use it unless you have a low power "e" model CPU -- http://www.amd.com/en-us/products/processors/desktop/athlon-ii#