Its doesn't have 6pin connector.
Then that confirms my suspicions. It is a small cheap 200W - 250W unit that is not designed for using a very powerful gfx card. I would be afraid to recommend a decent card for that PSU. Is this your PSU?http://forum.lowyat.net/uploads/attach-12/post-387212-1337430805_thumb.jpg
See if you can read the nameplate. Tell me the rating for the +12V rail.