http://www.newegg.com/Product/...x?Item=N82E16814130099
The 7600GT would be comparable in performance. The main advantage of Nvidia in this case would be driver support for Linux.
In the end it depends on what games you want to play though. Nvidia is quicker in some, ATI in others. One other good thing is that EVGA has a lifetime warranty versus the typically 1 year common with most ATI products(like HIS).
If this is for a Media Center PC or you will be watching a lot of Movies though, I'd go with ATI. IMO, ATI has better AVIVOHD with UVD compared to Nvidia's Purevideo. UVD and AVIVO HD is just better at processing HD content than Purevideo while Purevideo may be slightly better at processing Standard Definition content, giving (subjectively) better video quality under 480P content while ATI is more efficiet at 720P and 1080i/P content.