Thanks for all the suggestions folks! - confirmed my suspicions that Geforce 3 was the way to go.
Went shopping yesterday, and found my dream graphics card - the Elsa Gladiac 920 as I originally wanted. It is a Geforce 3 card, and has loads of impressive sounding numbers. It is bundled with a specially enhanced version of Giants: Citizen Kabuto - is this game any good? (Not that I bought it for the game

but it could be a bonus if it is worth playing)
It did cost me more than a weeks take home pay though. I felt a bit faint afterwards! Upgrade at the weekend - Abit motherboard, 1.1Gb Athlon processor, 256 Mb RAM and of course my lovely shiny graphics card.
So hopefully TOB won't be choppy like it is at the moment, and I might actually be able to run Arcanum....
So now I can put myself forward for a BGII/TOB multi without worrying that my PC will ruin it - it currently takes over 3 minutes to load a new location *groan* and the lag is incredible!
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Time is an illusion. Lunchtime doubly so.
Epona of The Laughing Hyenas
Proud winner of the 'Most Useless Post 250 Has Ever Seen' Award 2001. "I'd just like to thank my friends and family, without whom none of this would have been possible..."