Two 680s or one 780?

Male Person

Honorable
Dec 27, 2013
7
0
10,510
I was made my rig a year or more back and now want to upgrade a little to supply for a new screen that I have introduced. My problem is that my current rig has a MSI 680 power edition which i dont seem to be able to find anywhere at the moment as its discontinued.
Therefore I have two questions:

  • Would it be better to sell my current card and buy a new 780 card with the money (and a bit more) or should i go for another 680 and keep the old one to use in SLI
What 680 would go well with the MSI 680 power edition in SLI seeing as I cannot get the same card. I am aware most if not all 680s work together however I know the superior card will downclock to the level of the lesser card.
Thanks for the advice ;)
 

Male Person

Honorable
Dec 27, 2013
7
0
10,510
Ok i get that the 680s are the way to go.
Will my Corsair Builder Series CXM 750W Modular power supply be apt for two 680s? or will that need to be replaced. Sorry to ask more questions. Also what model would be recommendable.