I would get the 2gb and an evga 7900gs, and step up to a mid range dx10 card at the end of the month or when ever you can pay the difference for the dx10 card (just remember the step-up program only has a 90 day window after purchase). A 7900gs is a good card too so you shouldn't be disappointed while waiting a little while for a dx10 card. I was playing fear, oblivion, and bf2 on high settings at 1280x1024 with the 7900gs so its a pretty good card for the price.
And you didn't need to start a new thread for the newegg/tax problem. I would have just answered it in this post, if you asked here.
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