How is this rad?

http://www.petrastechshop.com/dadenblicext.html
How is this radiator for cooling a 7600GT and an E6600?

Eh, not the best choice. If you can only fit a single fan rad, I would suggest this: http://swiftnets.com/products/mcr120-qp.asp

A BIX is not going to cool both of those very well. The MCR120 is a better rad, but still is really not the best choice. Your better bet is going to be to use a MCR220 rad as the larger size allows for more surface area, or your best bet is to go with a PA160 if you are looking for a single fan solution. What is your situation as far as rad mounting is concerned? Is there a specific reason you are only looking at a single fan rad?