[Meelapo]

Need some advice...

Last week I bought a EVGA GTX 1070 SC. I've not opened it yet because I'm been debating on whether or not I should return it and buy an EVGA GTX 1080 SC. The cost difference is $310. I'm wondering if you guys and gals figure it's worth the upgrade or if that money would be better used elsewhere. For example, buy a new CPU or RAM or motherboard or pay $50 and get the EVGA 1070 FTW edition.

Here's what I have:
i5-2500K overclocked to 4.3 GHz
ASUS P8Z68-V Pro motherboard
32 GB of 1600 Mhz RAM
GTX 670

And how I game:
2560 x 1440
(aim for 60 FPS)

I'd like the setup to last me 3-4 more years. I know the CPU is super old and I know I'll have to upgrade soon but it seems that the delta between my CPU and a newer CPU is not that much vs a 1070 to a 1080.

Thoughts are appreciated!