Cpu and Gpu questions.

Assuming you mean for gaming i do a i5 3570k and either the 7850 or gtx 660/660ti. The i5 3570k is a much better processor than anything AMD has out right now. GPU wise either of those choices would be suitable.
 
err, WTF.

A better Intel CPU and a better AMD/ATI video card vs
A poorer AMD CPU and a slower NVIDIA video card.


Yeah....

1) i5 3570k with radeon hd 7850

http://www.hwcompare.com/13141/geforce-gtx-660-ti-vs-radeon-hd-7850/

At lower resolution the 660 Ti might pull ahead as it has an insanely over-speced texel rate (due to being a defected GTX 670 GPU, they have other bottlenecks internally).


The GTX660 Ti has much less 'spikey' gameplay though, as a result of having 112 texel units vs the Radeon's 64.
- Personally I'd lean towards the GTX660 Ti as I don't trust the first iteration of the 'GCN' Radeon HD's from AMD/ATI.
- http://techreport.com/review/23981/radeon-hd-7950-vs-geforce-gtx-660-ti-revisited/3