He will need OS X, minimum in order to run FCP 4.5. Did you mean 400 Mhz processor? In that case, it's too slow to run FCP 4.5, and also for the newer versions of OS X. He would need at least 512 MB of RAM.
Time to get a new Mac, sorry.
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"Prefiero pasar como ignorante cuando pregunto lo que ignoro, que pasar
como ignorante el resto de mi vida".
- A. Hauffen.
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