If the card is soldered to the motherboard of the laptop, then there is no option other to send it in for repair/replacement. Since we're talking about the 7600GT Go, I suspect the warranty has long since expired. If the graphics card is actually installed into an MXM slot, then I would only replace it with another Geforce Go 7600GT. Going with a newer/better graphics card may create driver incompatibilities, power issues, and overheating.
-Wolf sends