i would go definitely for d Duron.
Celeron was always from it's beginning a 'bad produced' processor that intel chosed to bring as a 'low cost' alternative (it's basically a normal Intel with it's cache memory 'hammered' to half size from a regular Pentium).
Latest reviews as showned AMD processors getting similar (n even better) performances then Pentium with same clock speeds.
i would go to d Duron
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