128mb card. My computer is AMD XP 1200mhz, over 400mb ram, and win xp os.

When I try to play Halo, and I havent tried another game, the screen flashs between the normal colors and red. Constant red flashes, I can't figure out what the problem could be, any ideas?

Check the monitor cable. This may be loose; this is what usually happens when that cable is damaged or loose. Let me know if this doesn't fix it.

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If builders built buildings the way programmers wrote programs, then the first woodpecker that came along would destroy civilization.

doesnt fix it

Does it ever happen on the desktop or just inside the game? You may also want to check to see if it does it for any other games. If so update your video card drivers. If it doesn't happen in other games also see if the game giving you the problem has a patch and try that.

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If builders built buildings the way programmers wrote programs, then the first woodpecker that came along would destroy civilization.

It doesn't do it with Counter-strike, just seems to be a halo issue.

You may want to see if there is a patch for the game, download and install it and see if that fixes your problem. Let me know if this doesn't work.

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If builders built buildings the way programmers wrote programs, then the first woodpecker that came along would destroy civilization.