Upgrading from GTX670 2GB SLI*2 on a budget

[daggarhawke]

Dear most excellent THW community,

What is the most cost effective way to upgrade a GTX670*2 SLI? These are 2GB vram cards. I game at 1440p with an i5 3570K. But I'm also interested in CUDA for scientific distributed computing, such as through BOINC.

I'm not looking at upgrading immediately, but will when I have the budget. Right now I'm interested in such questions as: what single graphics card (and/or pair of cards, though I'd prefer single) would be the least expensive upgrade to my current rig for both gaming and compute, either new or used? What are your thoughts on buying new versus used to save, or from the previous generation to save money?

Gratitude in advance for your assistance!

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Edit: if you have insights on the pros/cons of GPU computing with two cards versus one, feel free to comment.

 

[A12MO12]

I don't think a single card will beat out SLI 670s unless you go titan x or 980 ti (will be a very slim margin). I would recommend 1x gtx 970 and then save up to pick up another one later on. A single 970 should work fine for 1440p and once you pick up a second gtx 970 it will out perform the 670s.