If its not cable, then it sounds like a video card issue. I'd suspect monitor backlight was giving out, but you got the no signal onscreen. You need an x1950 Pro AGP anyway. I know two people that just bought the 512 MB Sapphire version and it made their AGP systems have some additional life. Costs about $250 if you can find it, but the card is so popular that it is frequently sold out.
-S
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