I recently bought this to replace the Dell heat sink compounds on my portable computer as I upgraded my processor.
One has to be careful to not use electrically-conductive thermal grease on chips which have small circuit features immediately on or next to them. While my processor module was completely immune to short circuits (Intel's packaging insulates the entire module, allowing electrically-conductive materials to be used), both my graphics chip and a bus chip were not as well designed, and since both also shared the heat piping system for internal cooling, I had to assure they continued to vent properly.
Fortunately, after some visiting to different websites, I found this to be the best to try. I was very impressed! My graphics chip now runs about 20F degrees cooler than before and the whole bottom of the portable feels much cooler.
Although I would recommend the electrically-conductive Arctic Silver for chips which have appropriate insulation (due to the slightly better heat conductivity it has), without a doubt I heartily recommend this compound for all other uses, and if you must, this would work fine on processor modules, as well.
Buy this and you won't be sorry.