==Where is the BIOS?==
{{WorkInProgress}}Technically speaking, there is no BIOS. Typical configurations of true embedded systems implement a bootloader instead. This software is executed by processor right after it comes out of reset. Like BIOS, bootlader is responsible of:# initializing the majority of hardware components - for example processor main PLLs and SDRAM controller# loading operating system kernel; once this step is completed, bootloader or any part of it is not involved anymore until next bootstrap.Bootlader usually implements a console - for example via UART port - that allows human operators to interact with the machine. This is extremely useful, for example, for maintenance operations and for development purposes.
==What about GPU?==
Modern PC graphics cards integrate a processor called GPU (Graphics processing unit) that accesses a dedicated SDRAM bank.