Is it possible to crossfire a gtx550ti 1gb with a gt630 2gb with an amd Athlon x4 860k processor?

Solution
With Nvidia they MUST be the same exact card (Or at least same exact model like a 550ti and another 550ti, same amount of cores and ram. They can be from different makers but it is best if they are exactly the same. You could use the 550ti as your main card as the 630 as a physX card?

only on AMD's can you crossfire different cards but they at least have to be in the same family. Like a 7770 and a 7790
With Nvidia they MUST be the same exact card (Or at least same exact model like a 550ti and another 550ti, same amount of cores and ram. They can be from different makers but it is best if they are exactly the same. You could use the 550ti as your main card as the 630 as a physX card?

only on AMD's can you crossfire different cards but they at least have to be in the same family. Like a 7770 and a 7790
 
Solution