In terms of overall gaming performance, the graphical capabilities of the Nvidia GeForce GTX 560 Ti Gigabyte OC 1GB Edition are massively better than the AMD Radeon HD 7660D + 6670 Dual.

The HD 7660D has no core clock speed set, so any comparison between Texture and Pixel Fill Rates is not currently possible.

The HD 7660D was released over a year more recently than the GTX 560 Ti, and so the HD 7660D is likely to have better driver support, meaning it will be more optimized for running the latest games when compared to the GTX 560 Ti.

The GTX 560 Ti has 1024 MB video memory, but the HD 7660D does not have an entry, so the two GPUs cannot be reliably compared in this area.

The Radeon HD 7660D + 6670 Dual has 760 Shader Processing Units and the GeForce GTX 560 Ti Gigabyte OC 1GB Edition has 384. However, the actual shader performance of the HD 7660D is 0 and the actual shader performance of the GTX 560 Ti is 691. The GTX 560 Ti having 691 better shader performance and an altogether better performance when taking into account other relevant data means that the GTX 560 Ti delivers a massively smoother and more efficient experience when processing graphical data than the HD 7660D.