Hmmmmmmm, It sounds like you've tried almost everything =(. My only guess is that NFSHP2 doesn't fully recognize your Radeon9700and is forcing you to run in crappy software mode where there is no 3D acceleration. Check on the box if it supports the Radeon. It sounds like your 3D card is giving the problems, I don't have any experience w/ ATI drivers but I think that might be the problem.
Also, a REALLY good thing to do is to find EA's NFSHP2 website and find the official forum and search to see if anyone has your same problem. In my experience searching forums for common bugs solves like 90% of all game problems.It's too bad cuz NFSHP2 is a really a kickass game. Good luck!
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