GTX 6xx serie with cycles?

Hi
I’m planning to buy a new computer especially for rendering. I noticed that the GTX 6xx serie is more common and 5xx is already more difficult to find.
But i was reading somewhere that 6xx cards are having problems with cycles.
Does any1 know if it’s still an issue? or was it already solved?

Hard to tell, as with every NVidia driver update you can get completely different result, you better get it with moneyback and try yourself. In theory, 6 serie is a bit less power hungry and have less efficient computational capabilities, but not catastrophic, like 30-20% slower than all expect from next generation.