I'm obviously missing something over here. Excuse me for my ignorance. But isn't a rom the actual game? it comes in .iso or .bin and such. All the games Ive got only has the rom. where can I get the bios from?

edit: okay figured it out and downloaded a bios file named scph1001.bin for the ps. does anyone of the bios files work or is there a specific one? because there are graphical issues in all the games I tried.