bios

lelunicu · 08-21-2019, 02:14 AM

hi,
the bios read all the hardware he find the the OS will read what bios found -then load the drivers.right?

pan64 · 08-21-2019, 03:53 AM

no. The hardware usually detected during the boot (of the OS), not by the bios. From the other hand the bios assumes some kind of hardware (like display, keyboard) just to be able to configure it.

rokytnji · 08-21-2019, 04:00 AM

Bios just informs things are wired in correctly first. Then some settings adjustments for fine tuning.

pan4 covered the rest.

Edit: Personal note to explain a little better. I changed out hardrive on a touchscreen asus laptop. I broke something on hardrive connection so bios does not see hard drive now.

So. Till I figure out what I broke. I am running the laptop on persistent usb drive instead of the internal hard drive.

lelunicu · 08-21-2019, 04:11 AM

why then if i disable a component in bios the os will not see it?

TenTenths · 08-21-2019, 06:14 AM

http://www.linfo.org/bios.html

jefro · 08-21-2019, 07:00 PM

If we assume legacy bios to being with....

Bios could in most modern cases have a way to "find" devices. May not however. May not fine all.

Now as to if an OS can use devices in legacy then I'd say yes even if bios didn't present it to the OS at boot.

ehartman · 08-22-2019, 07:28 AM

Quote:

Originally Posted by lelunicu

why then if i disable a component in bios the os will not see it?

That BIOS (Basic I/O System) normally only detects ON-board hardware, so to enable a plugin extension-board's hardware the onboard component of the same capability can be disabled.
The kernel will take over the list of detected hardware from the BIOS and then do its own scanning for all added/extra components.
For instance if you got a network adaptor ON-board and a plugin hi-speed one, normally you will get BOTH enabled. To always use the hi-speed one by default, you could disable the other one in the bios.

jsbjsb001 · 08-22-2019, 07:36 AM

Quote:

Originally Posted by ehartman

That BIOS (Basic I/O System) normally only detects ON-board hardware,
...

Not exactly true; if you have a PCIe video card, the BIOS still "detects" that, and in many cases has an option to select between onboard graphics or a PCIe add-in card for graphics - like my machines BIOS/CMOS setup program.

jefro · 08-22-2019, 04:22 PM

"BIOS still "detects" that" Most consumer cards have chips that report to bios. They can only do that if all things are favorable. Conflicts or power or resources could affect how it work.