Hello,
I want to upgrade my graphic card (GTX 460) to be able to perform GPU rendering. Currently, the renders are highly noisy even at very high render settings.
I am considering GTX 650Ti Boost card. NVIDIA GeForce Graphics Cards
Will this card be able to take care of the noise issues? 
Please suggest.
Thanks
In my opinion, anything below a 670 is not really worth it. For small scenes the 670 is OK but you certainly will not get noise free unless you are willing to spend a lot of money, i.e on a GTX Titan, GTX 690 or perhaps the upcoming Quadro K6000 (very expensive). For interior scenes, depending on the complexity will never really become noise free in the time it takes just to render it as biased using IR and LC.
If you are on a budget I would suggest the GTX 780, it is almost the same performance as the GTX Titan but with less memory at 3GB instead of 6GB. Anything less than this and unfortunately you will be wasting your time and wont see much benefit over an i73930K for example.
GTX 650Ti will be probably even slower for RT/GPU. Like James noted, GTX 670 is the minimum from 6xx series. If you want something cheaper, you can search for old GTX 570/580. These are still pretty good cards.
+1 !
I’ve here a gtx 670 (4gb ram) and an “old” 580(3GB ram).
The old 580 performs 1.4 faster than the 670.
If you can find a couple of 580, will be cheap and efficient.