@rpeterson ok, so the pcbios is sending characters to the serial port and CONSOLE_SERIAL is also sending characters to the serial port. This is what I’m guessing because of this post: https://superuser.com/questions/1358359/putty-serial-port-access-to-rs-232-console-showing-double-character-display-with

So I have to ask the question. Have you tested the fog stock ipxe boot loader? If PCBIOS is redirecting what would go to the screen out the serial port then that is all you should need. Now once you get the fog ipxe menu to display correctly, when you pick a menu item on the ipxe menu and bzImage and init.xz are loaded that is where the kernel parameters console=ttyS0,115200n8 come into play. You don’t need to edit bootmenu.class… just go into FOG Configuration->FOG Settings->Kernel Parameters and add in that line. It will be added to every computer that pxe boots into fog.