Well you could go the route of buying a new card for around £50 or $50.
But if your after something with a bit of kick for that money you could try your luck on e-bay.
For example a ATI 7970 card went for about £55 two days ago on e-bay.
Fully working may I add, and they are old but still very powerful, and keep up with most new games today.
You may have to turn a few in game FX off or lower a few settings in game slightly. but they still chug along at a decent frame rate at 1080p in most games.