be careful when looking to the usual places for updates for the AMD world. First... try not to get the combo updates that jump from 10.5.2 to 10.5.5. They don't work too well... they tend to freeze in the middle. Do you have the most up to date ASU? (still 0.5 as far as I know)...

Check: 1. When you run the normal Software Update, does it see all the possible updates?
2. Let the console run while you are trying to obtain the updates through ASU and report any errors.

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