For video editting you really do not need to worry yourself overly much on the video card. To be honest I'm not sure the vide card will make one ounce of difference to Premier pro. Certain effects in AE will make use of the GPU though so don't discard the idea of a better/faster graphics card entirely. But you're almost certain to get a better return on a faster processor and more RAM. If you have Premiere Pro and AE running together then I would consider 2Gb of RAM to be your starting point. I'm getting by with a 3GHz P4 but it's feeling a bit sluggish lately and I'm considering something new for the middle of next year maybe.

Also, something important but not mentioned is HDD space. You want a minimum of two physical HDDs. One for the OS and s/w and the other for video work. The first can be small (around 80Gb) but the video drive wants to be big enough for your work and (as you are using Adobe s/w) make your big drive an internal drive as well. If you phone Adobe support you'll likely still get told they only support internal drives rather than networked or external drives.

Other things you can do to get bigger bang for buck is not edit high def in native Premier Pro 2 as well. I'm sure it works ok but ther's better high def routes than plain vanilla PPro.

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