Though I don't have a direct answer to your question, I can think of a 
couple of reasons that HP might be suggesting some limitations to what hard 
drives their laptop can support.  If this is an older laptop, the BIOS may 
have limitations to what size drive it can correctly recognize.  The other 
concern would be how much heat the hard drive generates.  HP may be figuring 
that a larger and higher rpm drive will generate more heat than was factored 
into the design for this particular laptop.  A hard drive that isn't 
adequetely cooled is at a greater risk of failure.

Power consumption might be another concern; the importance of which would 
depend on how much you use the laptop on battery power.

This isn't to say that you can't use a Seagate drive, purchased from NewEgg 
for example, to save money, but there might be some good reasons for HP to 
steer you away from the biggest and the fastest of these models for your 
laptop.

These are mostly speculations; so, I look forward to the input of others on 
this question as well.

John Sproule

_____________________
Original Message:

Date:    Thu, 19 Oct 2006 10:00:34 -0400
From:    "James W. Cooley" <[log in to unmask]>
Subject: Which HD  for HP Laptop Pavilion zd7000?
On chat with HP they say I can only go to 80gb. They say I need Ultra
ATA/100 EIDE 2.5" by 9.5mm and suggest 40 and 50 gb, 4,200rpm and 5,400rpm.
Seagate has a line of Momentus going up to 120 gb and 7200rpm.  costing far
less than HP.  Can I use  the momentus drives?

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