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you answered a lot of these questions in you initial post, but there are more.
indicate what hardware you have or are reusing from another system (keyboard, mouse monitor, optical drive, hard drive).
do you need an operating system included? if have one what is it XP/Vista Win7 32 or 64?
does your budget include shipping ? if it does include a city or ZIP code
you mentioned dual screens... do you already have them? what resolution?