First of all, let’s see how much slower the Nvidia GeForce GTX 650 Ti 1GB is in comparison with the GeForce GTX 660 2GB, at their default clock rates:
The gap is quite large. The GeForce GTX 650 Ti 1GB is an average 37% and 40% slower than the GeForce GTX 660 with full-screen antialiasing turned off and on, respectively. The price difference between them is 37%, too. The 2-gigabyte version of the GTX 650 Ti wouldn’t be any better as, according to the benchmarks, the extra 1 GB of memory doesn’t provide any benefits.
It’s also interesting to check out the difference between the reference GeForce GTX 650 Ti 1GB and the GeForce GT 640:
The junior card is only half as fast as its cousin. Considering that the GeForce GTX 650 Ti breaks no performance records itself, the GeForce GT 640 is definitely not a gaming product. It is rather meant for multimedia PCs or can be used as merely a display adapter to output 2D image to one or several monitors.
Being somewhat more expensive, the Radeon HD 7850 does not compete with the GeForce GTX 650 Ti directly. However, we want to compare the fastest of our GTX 650 Ti cards with it: Zotac GeForce GTX 650 Ti AMP! Edition 2GB vs. Sapphire Radeon HD 7850 2GB.
The Radeon HD 7850 is superior in every test including Nvidia’s favorite Lost Planet 2. The AMD-based solution is an average 24% faster than the Nvidia-based one without FSAA and 27% faster with FSAA. The difference in retail price between the simplest Radeon HD 7850 and the Zotac is about 10%, so the former is preferable.
Being more expensive, the GeForce GTX 650 Ti 1GB beats the Radeon HD 7770 1GB:
The GeForce is 14 to 15% ahead across all the games, but the Radeon HD 7770 is capable of challenging it in a few tests.