‘Kay so, if anyone has ever wanted to play Fallout 1 and 2 and has had trouble with it because of the rainbow graphics and the screen randomly going black, well, I have the solution!
And it is the most roundabout fix ever, and it took me weeks of Googling to find it on this little tiny blog which I have now forgotten all the details of so I can’t find it. (If anyone finds the blog where this solution comes from, let me know and I’ll credit them.)
Okay so first, if you are on Windows 7 or Vista (which you are if you’re having this issue), you have to right click on your desktop and go to “Personalize.”
You will see the window with your themes in it. If you’re on Windows 7 (not sure about Vista), you’ll most likely have an “Aero” theme selected. This is the first part of the problem, as Aero does something weird to the Fallout games. Scroll down all the way to Windows Classic and select that. It’s ugly, I know, but these games are so worth it. You have to run in Windows Classic for this to work.
Next is the tricky part (not really that tricky, though).
Once again, right click on your desktop. Select “Screen Resolution.” You’ll see a button somewhere in the resulting pop-up window that says “Advanced Settings.” Click it. Another window with several tabs should pop up.
You’ll see a tab that says “Monitor.” Select that tab, then leave all the open windows there. Do not close any of the windows. Leave them open, then launch Fallout.
And voila! Your rainbow graphics should be fixed. Just do this every time you play, and you’ll never have to worry about that annoying problem again. This is great because it astounded my boyfriend, who’s been playing Fallout for years (since he was much too young to be playing these games, haha) and just assumed he would forever have to deal with the rainbow graphics.