Overclock3D has a review of AMD's latest budget card.
"By inserting new models at the peak of the range the pricing has crept down slightly on the rest of the available cards meaning you can get a hell of a lot of performance for your pound. With the HD6850 available for around the £135 mark and the GTX550Ti around £115 the days of being unable to get more than an asthmatic wheeze out of a value card are long gone as both will provide decent performance for the outlay.
Appearing beneath the HD6850 in the AMD range the new kid on the Value block is the HD6790. In the same way that going big with high-end cards has diminishing returns, so the same is true at the lower end. Eventually continually cutting down performance to reach a budget will stop having a good card for the money and rather just leave you with something that might run Freecell."