bobbothner :
@Frag Maniac: So you're saying my CPU would bottleneck the 970?
Also is there a big difference in performance between the old i7 cpus (example i7-3770k) compared to the newer ones? What's the difference? I'm really reluctant to change mobo+CPU+GPU...
It most likely would, yes, how much so, I don't know. If you were expecting same performance out of the 970 others are getting, you may be a bit disappointed. That is going to depend a lot on the games you play. Some are really demanding on the CPU. Others, not so much.
Between Sandy/Ivy Bridge and Haswell, no, not huge, but you don't need an i7 for gaming. You'd only be paying for HyperThreading (and excess heat if you leave it enabled), which does nothing for gaming.
The only time it makes sense IMO to go i7 is if it comes with a hefty clock difference, like the i7 4790k, which is Intel's only CPU that runs at a stock speed of 4GHz. And that speed is nice to have even if you plan to OC, because not all CPUs OC well. The 4790k runs hot though.
IMO 2016 will be THE year for big hardware changes. Nvidia will have Pascal with stacked DRAM, unified memory, and NVLink. Intel will have Skylake smaller die budget platform CPUs compatible with DDR4. MS will have W10 and Dx12. And the DDR4 RAM by then will be lower in price and latency.
One alternative to the 970 would be a 760, which start at around $180 new and is more suited to your CPU, but it's barely 50% more powerful than what you have if that, and prices on them anymore are not nearly as good bang for buck as the 970. The 970 is roughly 2.4 times as powerful as the 7850, and even if the bottleneck knocks that down to 2 times as powerful, it's still a HUGE leap in performance and you'd already have a GPU good enough for your CPU upgrade when you get around to it.
Bottlenecks aren't as bad as some think, I just wanted you to know what to expect. Prior to my 7970 I was running a mere GTS 250 on my i7 950 CPU, but it played games pretty well anyway. Well, until they went into graphics overload a couple years ago anyway.