Guys who know how to develop custom rom ?

  1. See my reply to your other post.
  2. ROM's (usually the BIOS) are custom chips. Some are PROM's (Programmable Read-Only Memory), which must PC/Laptop BIOS chips are so they can be updated when necessary.
  3. To alter a PROM you need a programmer software tool to write and compile the code (usually assembly language) and a PROM burner, or the program to update your system PROM with the new code. Note that this not something for the inexperienced or you will likely turn your system into a nice door stop...