Looking at upgrading - new CPU or GPU?

Adz85

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Jul 4, 2008
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Looking at upgrading my machine for gaming purposes.
I have an E8400 and HD6850
Would I be best served by upgrading the GPU or CPU?
I'm thinking Intel Core i5-3570K OR 7850/70.
Which will make the bigger impact to my gaming?
I want to be able to play new FPS games, don't really care about getting to MAX settings, just want to get rid of the poor fps I'm starting to get with my aging parts.
 

Adz85

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Jul 4, 2008
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I know both are better than what I have :) I'm really only looking at doing one or the other at the moment.

Budget is probably $400 simply because I'd need a new mobo if CPU is the better to go with. I usually go for the $200-250 range of GPU.

I guess I'm asking, if I get a 7850/70, is my E8400 a bottleneck for gaming? If so, I'll probably go for the CPU option.
If current CPU is fine, then I'll go for a better GPU.