A PCIe heatsink is specifically designed for a PCI Express (Peripheral Component Interconnect Express) card, which is a high-speed serial computer expansion bus standard. Format specifications are maintained and developed by the PCI-SIG (PCI Special Interest Group), a group of more than 900 companies that also maintain the conventional PCI specifications.
As a PCIe card has a height restriction of 14.48mm this means that fin height is fairly limited for the PCIe heatsink, especially when considering that a typical BGA chip height is around 3mm including solder balls.
Airflow should also be considered for a passive solution, and if there is a spare slot then it is worth considering our PCIe Fansink or BGA Fansink line.