I have stated time and time again to my users why I do not use copper shims. This is a prime, grade A example of what can, will, and does happen with shims.
This laptop came in from an owner whom sent their laptop from Australia. This copper shim was placed on his system from a laptop repair center from the United States that he used off of eBay. I am not naming names of the offending company, but I will post the pictures.
DO NOT USE COPPER SHIMS! As the pictures display, this copper shim chipped the video chipset.
If you need your laptop fixed, check this link: http://applelogicboardrepairservice.com/pricing/laptop-bga-reflow/