Look no further than Free PC Tech-the web pages of this list.
There are excellent guides and article on everything PC.
http://freepctech.com/pc/001/installing_ide_devices.shtml
The HP website can also be very helpful. Support for your model is at:
http://www.hp.com/cposupport/prodhome/hppavilion6418.html

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I need to install brand new hard drive, and also installing existing hard
drive as second one on HP8380.  Rather than asking all sorts of questions
now, about how to do it (or attempting to do it, then asking all sorts of
questions when the attempt goes south) can you guys (and dolls) point out
some great (beginner) sites on how to install hard drives?  You know, the
ones somewhere between "Don't try this at home" and "Advanced Initiatives in
BIOS Idiosyncrasies Caused by Static Electricity During Installation".

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