Form Factors Under Development
In addition to the cards and slots that are defined with the PCI Express Card Electromechanical spec, there are other form factors currently under development by various groups. These form factors are usually designed for a particular class of applications and thus have different constraints. A card designed for a server application for example, will typically have a bigger power budget and more space available than one designed for a mobile application. The specs for these form factors were still under development at the time of this publication and are therefore subject to change.
Server IO Module (SIOM)
The PCI SIG is currently developing a module for the server environment called the Server IO Module ...