As Microsoft released slimmer revisions, they updated the MCPX Boot ROM:
To resolve these issues, users can try:
This is the physical method. You dissolve the epoxy package of the MCPX with fuming nitric acid, exposing the silicon die. Using a high-resolution microscope, you photograph the metal layers. The Boot ROM is an array of transistors (mask ROM). You manually transcribe the bits. This is how the first MCPX ROM was dumped in 2009 by the infamous team "Tiros." Mcpx Boot Rom Image