check out this link, its really worth a look http://www.pcper.com/article.php?aid=180
The driver problem you have may not be with the new ATI but a conflict with prior driver (nvidia drivers are often a major problem... ) that...
I forgot to add in my prior reply above, one of the easiest tests is to take (I assume your running windows) the pc and boot into windows safe...
It would be easier to give you good advise if you could describe the following in you post: 1) Does it happen randomly? What are you doing when...
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