With a significant technical event coming you go by that event and not necessarily the 3-54 year life you hoped to get out of hardware in the past.
Windows Longhorn 64 bit will be here in 2006 or 2007 likely. That will immediately alter the landscape for what is out currently and will trigger purchases at that point in time (once it it mainstream).
That is what Intel and AMD are counting on and they are racing to have the 64 bit chips ready for that -- 2 cpus per chip -- the Athlon 64 is out now but 2 years from now there will be many other improvements (bus speed, new video card interfaces, faster RAM Speed, etc)
Thus I would not spend over $1500 or at most $2000 on any notebook right now ...............(unless you want an Apple Powerbook)
How often should a laptop be replaced?

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