Let's make a few things clear.
CAPs are cumulative. You're only recommended to uninstall the old one when you install a new one, because it would create multiple entries in your add/remove programs list. Why? Because of the stupidity of both Microsoft and AMD.
CAPs are built into the drivers as well. The separate package was invented for a simple reason. When a new game gets released, it's easier to make a new CAP package than recompiling the whole driver set. In reality it doesn't work of course, as AMD is usually very late for the party when there's a new game, and also usually needs a hotfix driver as well to make it playable.
However, the theories are still in place.
Suggestion: Forget about CAPs, install the latest non-WHQL (called beta) drivers everytime. Or don't update your drivers only your CAPs.
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