I have an ATI9550 and my experience with Dapper is very positive. The difficulty of installing ATI card under Linux and Ubuntu are pretty much referring to more than 1 year ago. Since beginning of 2006, the effort of ATI to make easy the integration of their driver with the various Linux distribution is giving good results.
For sake of truth, I found that the only howto really working is this:
I suggest to use the Method 1. It works, hassle free, guaranteed. There is really no reason to use method 2, unless you are a masochist. Using method 1, the driver will be automatically updated everytime the system will be updated. If you use method 2 then for every kernel update (3 times a month at least) you have to re-compile the driver.
Anyway, the fun with Linux is that you have the control and you can choose, so method 2 can be fun too.
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