Well, at first glance, I don't think it would be "worthwhile" to convert your external HD to an internal HD. And I am looking at it from not only a techinical stand point, but also a purchase price stand point too. Now-a-days you can go out and purchase a brand new internal HD for a fraction of the cost you most likely purchased the external. However, all this being said, I don't particularly know any of the specs of your "3-year old computer," nor do I know any of your user habits for what the system is being used for. Lastly, without knowing any of that information I would go out on a limb and say your best bet is to purchase a new internal HD (if your looking for more room) and install it as your master drive, (optional: if there is a second bay, I would install a second drive internally to use as a backup) and use the external as an external backup drive.
I have an older (3 years) Dell Dimension with an 80 g IHD, and use a Maxor 200G EHD as a backup and storage space. Is it worth considering removing the HD from the EHD case and using it as an IHD? My thoughts are adding some security and lessening the chances of an accidental drop or other unnatural disater.
Randy

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