Well after a bit more digging I came across some charts to compare video cards. Couldn't find the 256MB Nvidia GeForce 7300LE TurboCache graphics card, so chose 6800 version hoping it's a lesser model
Tom's Hardware Guide Processors: VGA Charts
From this it appears the Nvidia card produces nearly 3x frame rate per sec. If this is correct I would assume it's worthwile spending the extra ?