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Hawk,
I'd only add to whats been said, by suggesting dropping in a vid card as a test. Any nvid or ati card of recent years would do. Your local puter assembly business should have something older for peanuts or a friend who'll lend his to test.
As you've said it should work as is but if the tech wont give you a replacement mobo, any 9 series ati or G4 onwards nvid is your cheapest solution.
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