No way to say without knowing what your existing PC is and whether or not it can actually handle a 1TB drive.
So first we need Make and Model of the PC. From that we can deduce what kind of hard drive interfaces it has.
If the PC has no make that is it was put together by you, then we would need the interfaces it has for hard drives, or at the very east the motherboard it has.
Being 2004, my guess would be IDE HD connectors which would mean you need a SATA PCI card as to my knowlede there are no 1TB drives with an IDE interface. However at that age it won't likely support such a large HD.
Do your really need a 1TB drive, how about 2 500GB drives instead?
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Phil AKA Vacunita
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Ignorance is not necessarily Bliss, case in point:
Unknown has caused an Unknown Error on Unknown and must be shutdown to prevent damage to Unknown.
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