Hello, the last night i was looking inside the mobo of my old NCR machine and i have seen an empty square brown socket like a BIOS socket but my computer has a BIOS installed on-board . Why i think that the machine has two BIOS? that is because a man that has 5 machines like mine wants to make a experiment in a university and he said that the BIOS of that machines was removed and he needs a copy of the BIOS software, so i have looked inside the mobo to see what type of BIOS chip he needs and i have seen no BIOS chip with the exception of that empty square brown Socket like the one in this picture.

The on-board BIOS is very limited, it can't detect and boot CD-ROMs and doens't have other functions like modern BIOSes (the machine is from the year 2000). I am thinking that the NCR machine has a basic BIOS and a posibility to put a more advanced BIOS in that empty socket that disables the other BIOS. Can be this posible?

The machine has a writing in the front that says "NCR model 3501" and a Phoenix on-board BIOS

A BIOS chip is just a programmable IC. It could have any function it was programmed for, not only a BIOS program.

I don't know of any machine that has two different BIOS chips. Some newer board have a backup one to rewrite the BIOS program to the main one should it get corrupted or erased, but can still be on the same IC.

It wouldn't make much sense either unless maybe you had two different hardware setups you wanted to switch between at boot without ahving to reconfigure the BIOS.

Also, many circuit boards are designed and built to accomodate different set-ups. It is quite common to see a printed circuit board (any model) made for one country (US) and then the same board with different configuration set up for another geographic area .

I have more information about that machine:
Is a NCR mobo model 745X-35XX

The mother has a very big card plugged in a very big slot and this big card has the 2 PCI and 2 ISA expansion slots, a CR2032 battery that feeds the BIOS, and the on-board Phoenix BIOS, in the motherborad is the on-board video hardware (with a VGA interface and a LCD interface), the on-board LAN port (it doens't appear to work), two on-board Serial Ports, the two on-board PS/2 for keyboard and mouse and another CR2032 battery (why another battery? What is feeding?).

The on-board LAN port is not working, Can be this brown socket the BIOS of that LAN port? or is another socket for another main BIOS?

It looks like boards similar to this are mostly used in POS (point of sale) computers. It could be configured for a specific use such as scanning bar codes etc.
The second battery could be for any other device that requires a clock signal.
Do some research in NCR POS systems and you might be able to find a similar setup.

I know that this machine is only for comercial business only but i use it for old DOS programs but now i've started my investigation on this type of hardware to learn more about it.

Thanks to squirrelnmoose i know a little more about this hardware.

Maybe i talk like a caveman because i don't speak to much english