You should be fine! It will run BUT definately NOT on the high settings! Your video card is the same as mine (as much as I hate to admit I have a TNT2!) So, if you get a chance get a new video card! ( I'm hopefully getting Gforce3!) And an extra 128 RAM wouldn't go astray either!
Also, like Echo said, I hope you ment 40gb! Otherwise your going to get a surprize when tring to install the game!!
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Close isn't good enough unless you throw a grenade!