My Monitor turned all purple, pink, and green. (Mac OS 8.6)

[InsectorX]

I recently downloaded a new game for my Macintosh 8600 running 8.6, called Skullkeep II.  I was playing it and i wanted to change the volume, so I pressed command+tab to switch to the finder for a second.  But the screen and windows were all pink, purple and green in areas.  I didn't think much of it and changed the volume, and pressed command+tab to go back to the game (had normal colors in the game).  But when I quit the game, my finder still had all the messed up colors.  I then restarted the computer, and it still was messed up.  It even had the messed up colors in at the "Mac OS 8.6" splash screen, while loading extensions. 

What could be the problem?  I don't want to reinstall my OS, I just got it perfect.  I will back up next time.

Edit:  this also happened once before on this computer, but I fixed it by reinstalling the OS.  Not the best solution, but it worked.  But since this is a repeating problem (under the same circumstances, but a different game), I would like to learn where the problem lies.  Thanks  all

[ovalking]

I've had this type of trouble before, usually with games, where the colours go all wrong after switching apps mid game, or even after quitting.
I don't really understand what's going on, but know many games use custom screen drawing 'techniques' (for speed reasons) which may well be contributing to the problem.
A restart has always resolved this for me.
You could try checking the Preferences folder - try removing any relevant files that have been updated since the problem arose.
Could also try zapping the PRAM.
An OS reinstall would be a last resort for me.

[InsectorX]

I've had this type of trouble before, usually with games, where the colours go all wrong after switching apps mid game, or even after quitting.
I don't really understand what's going on, but know many games use custom screen drawing 'techniques' (for speed reasons) which may well be contributing to the problem.
A restart has always resolved this for me.
You could try checking the Preferences folder - try removing any relevant files that have been updated since the problem arose.
Could also try zapping the PRAM.
An OS reinstall would be a last resort for me.

Zapping PRAM didn't fix it.  And I deleted any preferences file that I felt was relevant to color, monitors, that game, etc.  But its still happening.  I guess I should keep deleting preferences until i find it.  Any advice?

EDIT: I just emptied my preferences folder into a backup folder.  I then rebooted to computer to let it make new preferences files for everything, and the computer screen is still all messed up.  So, I'm assuming that means that it's not a preferences file doing this?

[geforceg4]

Are u sure your video card is seated properly?

[ovalking]

EDIT: I just emptied my preferences folder into a backup folder.  I then rebooted to computer to let it make new preferences files for everything, and the computer screen is still all messed up.  So, I'm assuming that means that it's not a preferences file doing this?

Well that is a strange one! Problem not in the prefs folder nor in PRAM.
I guess you could try reinstalling the Monitors CP.
Have you tried booting off another system folder to at least prove hardware?

[IIO]

I've had this type of trouble before, usually with games, where the colours go all wrong after switching apps mid game, or even after quitting.

games usually patch the system palette (it´s just a [clut] resource or similar)

not sure if there is a better fix but re-selecting the color settings in the OS should fix that.

[InsectorX]

I guess you could try reinstalling the Monitors CP.
Have you tried booting off another system folder to at least prove hardware?

I'll try reinstalling monitors cp.  But I just booted from my Mac OS 9 Partition, and I'm not having this problem there.  So it's not a hardware issue.

[InsectorX]

not sure if there is a better fix but re-selecting the color settings in the OS should fix that.

Which color settings are you talking about?  Colorsync profiles?  Appearance CP?

[InsectorX]

SOLVED:  I opened Monitor & Sound Control Panel.  Went to Color, and changed my colorsync profile to something else, then back to my original one.  Fixed the problem. 

Thanks for all the help!