Seems to me that the defining condition of your wish list is/are the most dificult to get.
The easier ones can than fall into place.
The memory would be easy to find --but that depends on whether you'll settle for PC2700 or want more.
The potential deal makers-breakers is the Gfx controller you specified, I would think.
Also, getting a 120 G 2.5 HDD alone is an acheivement --but at 7200 rpm, well that alone imposes a huge hurdle. Also, that would be a huge battery burner, so you'll probably want several batteries--maybe two installed at once. Now compound that with the posibility that 120 g at 7200 needs two HDD's, and space grows astronomically.
My guess is that you will need to loosen these restrictions to get a chance at the project.
Can the video controller be subtituted for ?
Do you need such a large HDD for video editing? Otherwise, just burn the files.A DVD-onboard burner would probably help out.
You haven't said what you want to use this dream machine for, and that would help to know.
Also, do you plan just to move it around and use only the the AC adapter ?
If so, building your own lt.weight alum microPC with a "folding-flat" 15" LCD might help out. With the speed you seem to be looking for, I would think it would be near impossible to find a laptop screen that wouldn't "ghost".
Good luck, anyhow.
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