Replacing old GPU budget 200-300$

[YoYoman_92]

Can I put a (link below) or higher!

http://www.newegg.com/Product/Product.aspx?Item=N82E16814130833

In this system?

http://www.tigerdirect.com/applications/SearchTools/ite...

Another link to this system:

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Inside the system:

http://images10.newegg.com/NeweggImage/productimage/83-103-638-08.jpg

Also is SLI an option?
If not possible what other parts would I need to get to make SLI possible.

Thank you!

 

[dottorrent]

What's the CPU and PSU? Need more detail to make a recommendation(s) for your upgrade.