Crossfire X x16 & x4?

Hey, I built my PC last October and my motherboard is the ASUS P8Z68-V LX. I want to put 2 AMD cards and run them in crossfire. I have 2 PCI-E slots. One runs at x16 and another at x4. I also run the Core i7 2700k @ 4GHz. Would i be seeing any performance drop or should I just buy a GTX 650 Ti Boost instead of 2 AMD cards?

Thanks!

Just buy a more powerful AMD card? That'd be a good option. Crossfire and SLI both have issues with compatibility anyway but it is possible to do, just the one in the x4 slot won't be doing much.

Do you know of any mid range good AMD cards?

Mid range AMD cards are : 7850 , 7870. I'd get the 7950 right now

http://www.pixmania.co.uk/uk/uk/12838275/art/generique/radeon-hd-7950-oem-3-gb-g.html

http://www.pixmania.co.uk/uk/uk/12638311/art/generique/radeon-hd-7870-oem-2-gb-g.html

A single card solution is always preferable to a dual card solution.

This is a good card.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814161404