No, I would suggest you build a new PC. A computer that old wouldn't be worth upgrading in the first place, because your CPU would so bottleneck your graphics card. Plus, 256MB of RAM isn't enough these days, and I don't think your CPU can fully utilize DDR400 which is the bare minimum for a modern gaming system. Plus, if its a manufactured PC, usually everything is proprietary and there is no AGP slot, so upgrading cannot be done.