Yes, it all depends where you start; a similar program written as a boot sector would be quite short, but by the time you've got there a lot of BIOS and ACPI code has already run.

If you want to start from the very beginning of bootup, you do indeed have to start by turning the RAM on. See http://www.drdobbs.com/parallel/booting-an-intel-architectur... which I found for answering https://electronics.stackexchange.com/questions/311832/can-a...