"When it comes to proprietary drivers, AMD has almost
completely eliminated their dependence on the xorg.conf and NVIDIA
too is eliminating their need of this method for configuring the X
server. With the fglrx Linux driver, ATI/AMD has developed the
AMDPCSDB, or the AMD Persistent Configuration Store Data-Base. The
AMDPCSDB, which is somewhat modeled after the Windows registry, is
their proprietary replacement for managing all persistent
display/graphics-related options."