It’s very interesting article giving an understanding of how Intel Architecture-based systems work – The Pre-Pre-Boot, an overview of power sequencing, mode selection, switching processor operating modes and more and more systems work facts you every day use but attache no importance to it.
Taking a lot of little steps along a path is a good analogy for understanding boot flow in Intel Architecture-based systems. The minimum firmware requirements for making a system operational and for booting an operating system are presented in this article. The vast majority of systems perform these steps in this article to do a full or cold boot. Depending on the architecture of the BIOS, there may be multiple software phases to jump through with different sets of rules, but the sequence for waking up the hardware is, at least in the early phases, very much the same.
read article here – http://drdobbs.com/article/print?articleId=232300699&siteSectionName=
