ThermalV :
Paired with a 4670k which would be the better option? A single 760 seems to give good performance at 1080p so it wouldn't matter so much if SLI didn't function in certain games.
I am assuming from the original post that you are gaming at 1080p. If that's the case TechPowerUp offers some insight into how much more performance the GTX 770 gets over the 760 at 1080p gaming.
The stock GTX 770 has a 21% performance boost over the stock GTX 760
according to these charts.
The EVGA GTX 760 comes up only 13% under the stock 770
in these charts.
Taking into account that you can overclock the aftermarket GTX 760's you can almost close that gap to get 770 performance out of a 760 or at least come close to a non-noticeable difference. Some level of AA may still be unattainable on the 760 but for 1 monitor 1080p gaming the GTX 760 offers greater value while the 770 offers better performance.
In the end the most given solution is to get the best single card one can afford then go SLI in the future if performance levels are not reached (or if there's a good clearance sale
) if your case/PSU can handle it.