You don't specify how much ram you have. It's not the videocard that's important, but the actual ram of your system. And it's also a question how much free ram you have, in other words: what is also eating your resources. Even on a mac (OS9) you will have to find a block of memory that you can assign. STARTSystem can tell you how much ram you have

I have tried prudent planning long enough. From now I'll be mad. (Rumi)