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Start a computer without BIOS

By planetcode_2 ·
Can any body please tell me the behavior of computer hardware in such a case when there is no Software (OS) or firmware (BIOS) etc in it

I want to know the power behavior in such a case. i.e. when we give power to the computer then what would it affect on the hardware components. I mean what do they do?

Before the power they were sort of dead and after getting power whether they start to expect something or go on to some known state?

what is the Phenomenal change after the power up.

Can i get any information regarding this ??

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The components aren't going to do anything.

by CharlieSpencer In reply to Start a computer without ...

Well, maybe the video card, but until something tells them what to do, all they're going to do is consume electricity. Contact the BIOS manufacturer and ask for a bootable firmware disk. Even that may be trouble, since the BIOS won't be there to tell the hardware where to boot from.

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In Hardware

by oldbaritone In reply to Start a computer without ...

Specifically, the CPU.

When the CPU starts up from "cold" (power off) It simply clears itself and begins program execution at a specific memory location, like FFFF0h. That's where the system BIOS ROM should be. It runs whatever is there.

If there's nothing there, the processor will probably read an invalid instruction and halt. Instruction FFFFh is not a valid intel microprocessor instruction, and that's what it usually reads from empty space. The normal response to that is to disable interrupts and halt.

Then it just sits there, using power and doing nothing.


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