How I got 3 monitors working on 9010MT

Today I was trying to figure out how to set up a third monitor on my 9010MT, and looked at a LOT of posts on a LOT of threads on this forum and on others. Some people have gotten it to work and some haven't and there are a lot of opinions about how to do it (or not). I'm going to post how I got it to work, for the next person who comes looking. It's easy to do once you know how, but it's hard to figure out.

I have an old cheap Radeon card (DVI + DP) in addition to the on-board graphics. I have one monitor hooked up to a built-in DP port (display 1 in Windows 8) and two others hooked up via the Radeon. A configuration like this prevents the pc from even starting if you don't use the "multiple monitor" setting in BIOS that the documentation mentions. Problem is, you can't see that option if your video setting is set to "auto." When I was at that BIOS screen, as soon as I moved the cursor to change from "auto" the "multiple monitor" option appeared. I selected it and exited BIOS and everything worked after that.

Getting the monitors configured in Windows so my cursor would move from monitor to monitor the way I wanted to was as hard as getting all 3 monitors to work, but once you get all 3 of them up you can figure out the rest.

I don't know if this would work using all 3 of the onboard ports, because I needed the DVI on the Radeon card. But I think the most important thing to know is how to enable the "multiple monitor" setting in BIOS.