As a retro computer collector I’ve found out several things about those old computers. One of those is the IBM 5150. And sometimes it’s hard to find information about configuration and what’s possible and what’s not. So I will dedicate this post to findings for my (but also your) reference.
IBM 5150 mainboard dip switches
I replaced a monochrome videocard with a color graphics card. If you turn on the IBM you will see a big cursor blinking and doing nothing else. You need to change the dip switches on your mainboard. Set dip switch 5 to ON. See schematic above.