What operating system are you using?
Before you swap out the hard drives, to clone one to the other, your first going to have to have a letter assigned to the second hard drive and run them both at the same time.
I recomend using Norton ghost, as it is very reliable.
here is some info that you might find a little helpful
http://h10032.www1.hp.com/ctg/Manual/c00133452.pdf
From what you say, if the new hard drive isn't going to fit in the slot, you may have to exchange it for another one.
Unfortunately, some notebooks drives, hard drives, cds, dvd, etc
are vendor specific, meaning you have to use theirs.
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