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You need to buy a new video card. Any agp 1.5 volt card should be ok. Do not buy a 3.3 volt card, as this will fry your mobo.
The voltage of the card does not affect it`s ability to run at either 4, or 8 times agp.
Obviously the ammount you spend will depend on what you want to use the card for.
If you use the search facility at the top of any page you will find lots of recommendations for videocards.
Regards Howard :wave: :wave: