The 5670 is better than the both versions of the 5570 (the one with GDDR3 and the other with GDDR5). It's somewhat equal or close to the "old" Nvidia 9800GT in therms of performance, but uses lot less power and exhaust lot less heat. Plus the card has DX11 capabilities. It's slower than the 5750 (it's not a very big difference). It costs 99$ (you may find lower prices), while the 5750 costs 130-140$.