Why is the keyboard not working in the BIOS settings?

Question

Iron

Computer with win XP, mother ASUS p5-kpl-am se.
The built-in network stops receiving IP via DHCP after a reboot requires the installation of drivers, installing the drivers does not help.
I installed a network D-link DFE-530TX, the same thing, even if you can install the drivers, the network one does not work, and after a reboot it falls off, but it’s still unknown what the reason is, this network one seems to have problems with win XP, another unfortunately no.
And then I discovered a very strange thing, rebooted, entered the BIOS settings - the keyboard does not work, before the BIOS settings and after loading the OS - the keyboard works, I tried different PS / 2, USB, USB through the PS / 2 adapter, flashed the BIOS, everything is the same and also, before calling the BIOS settings, it works, it works in the OS, it’s not in the BIOS settings, you can even run the built-in utility for flashing the BIOS and the keyboard works there, it doesn’t work only in the BIOS settings, it doesn’t even respond to Num Lock.
When I start pressing F8 at boot, the choice opens from what to boot, I select the USB CD-ROM, after that I barely have time to notice the invitation to press any key to boot from the disk, the choice of how to load the OS in safe or normal also quickly jumps, the default option immediately works in usual.
I tried to install win 7 on top, the installation hung at the last stage of "installation completion", or rather, not quite to hang, the keyboard seems to work, there are some accesses to the hard disk, but after an hour of waiting, nothing has changed, after rebooting the installation rolled back.
So I don’t feel sorry for throwing this mother into the trash, since, in principle, it’s old, but maybe there is some kind of secret?

Answer 1

Looks like a hardware issue.
Disconnect everything from the mother except the processor and memory, connect the keyboard and monitor and try to enter the BIOS.

Answer 2

This is a reason to upgrade to newer hardware, to the same Haswell, the pro / memory / mother kit recently cost me $ 213 in Kyiv