I'm telling you to follow naquaada's helpful hint to using ASU to build working updates from already-downloaded-from-Apple software.

see here for this topic.

it doesn't require you to put anything IN the AMD Software Update, just your Downloads folder... make sure you drag the .pkg file from the image you downloaded from Apple to it. Then run ASU but select to modify a different update and it will download that update to your Downloads folder and move BOTH .pkg file updates to a temporary folder to modify them separately. you should then be able to install 10.5.5. Also, note that you should have at least a 9.4 kernel and system.kext file before you can update successfully. Too many people notice glitches in their systems after the update if they don't do this. The latest beta voodoo kernel and 9.5 system.kext file work just as good for myself too.

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