Second 660 Ti for SLI or GPU upgrade...?

tristanbane

Honorable
Oct 3, 2013
21
0
10,510
I haven't kept up with PC news for a while since I built my own about a year ago.
I chose the 660 Ti and it has been serving me well...
But now I feel like an upgrade is impending...

Would I gain more performance out of a second similar unit (~$280) in SLI or should I upgrade to a GTX 780 that I recently found out about (selling the current one in its place, of course)?

I'm also concerned about the PSU as I've never done an SLI build... Would I have to upgrade that too? (See below)

Some stats:
CPU: Intel Core i5-3570K Quad Core 3.4 GHz
GPU: EVGA GeForce GTX 660Ti 2GB 192-bit
RAM: G.Skill Ripjaws X Series 8GB (2x4GB)
PSU: Seasonic M12II 620 Bronze 620W